{"id":16400,"date":"2026-04-07T14:32:13","date_gmt":"2026-04-07T07:32:13","guid":{"rendered":"https:\/\/mb668s.com\/cam-nang-7mb66-xoc-dia\/?p=16400"},"modified":"2026-05-28T12:10:23","modified_gmt":"2026-05-28T05:10:23","slug":"dsa-la-gi-trong-lap-trinh","status":"publish","type":"post","link":"https:\/\/mb668s.com\/cam-nang-7mb66-xoc-dia\/tu-van-nghe-nghiep\/dsa-la-gi-trong-lap-trinh","title":{"rendered":"DSA l\u00e0 g\u00ec trong l\u1eadp tr\u00ecnh? Hi\u1ec3u v\u1ec1 c\u1ea5u tr\u00fac d\u1eef li\u1ec7u v\u00e0 thu\u1eadt to\u00e1n"},"content":{"rendered":"\n

Khi b\u01b0\u1edbc ch\u00e2n v\u00e0o th\u1ebf gi\u1edbi ph\u00e1t tri\u1ec3n ph\u1ea7n m\u1ec1m, h\u1ea7u nh\u01b0 ai c\u0169ng t\u1eebng nghe c\u00e1c \u0111\u00e0n anh nh\u1eafc \u0111i nh\u1eafc l\u1ea1i v\u1ec1 t\u1ea7m quan tr\u1ecdng c\u1ee7a n\u1ec1n t\u1ea3ng t\u01b0 duy gi\u1ea3i thu\u1eadt. V\u1eady DSA l\u00e0 g\u00ec trong l\u1eadp tr\u00ecnh<\/strong> v\u00e0 v\u00ec sao ki\u1ebfn th\u1ee9c n\u00e0y l\u1ea1i tr\u1edf th\u00e0nh th\u01b0\u1edbc \u0111o n\u0103ng l\u1ef1c \u1edf c\u00e1c v\u00f2ng ph\u1ecfng v\u1ea5n k\u1ef9 thu\u1eadt? B\u00e0i vi\u1ebft d\u01b0\u1edbi \u0111\u00e2y s\u1ebd gi\u00fap b\u1ea1n nh\u00ecn r\u00f5 b\u1ea3n ch\u1ea5t, c\u00e1c th\u00e0nh ph\u1ea7n c\u1ed1t l\u00f5i v\u00e0 c\u00e1ch b\u1eaft \u0111\u1ea7u h\u1ecdc DSA m\u1ed9t c\u00e1ch b\u00e0i b\u1ea3n, c\u00f3 l\u1ed9 tr\u00ecnh r\u00f5 r\u00e0ng.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n
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\u2013 DSA vi\u1ebft t\u1eaft c\u1ee7a Data Structures and Algorithms (C\u1ea5u tr\u00fac d\u1eef li\u1ec7u v\u00e0 Thu\u1eadt to\u00e1n).<\/p>\n

\u2013 L\u00e0 n\u1ec1n t\u1ea3ng cho t\u01b0 duy gi\u1ea3i quy\u1ebft v\u1ea5n \u0111\u1ec1 v\u00e0 t\u1ed1i \u01b0u hi\u1ec7u n\u0103ng ph\u1ea7n m\u1ec1m.<\/p>\n

\u2013 Big O Notation d\u00f9ng \u0111\u1ec3 \u0111o \u0111\u1ed9 ph\u1ee9c t\u1ea1p th\u1eddi gian v\u00e0 b\u1ed9 nh\u1edb.<\/p>\n

\u2013 L\u00e0 ti\u00eau ch\u00ed \u0111\u00e1nh gi\u00e1 quan tr\u1ecdng trong v\u00f2ng ph\u1ecfng v\u1ea5n k\u1ef9 thu\u1eadt \u1edf c\u00e1c c\u00f4ng ty c\u00f4ng ngh\u1ec7 l\u1edbn.<\/p>\n<\/div>\n\n\n\n

1. DSA l\u00e0 g\u00ec trong l\u1eadp tr\u00ecnh?<\/h2>\n\n\n\n

DSA l\u00e0 c\u1ee5m t\u1eeb vi\u1ebft t\u1eaft c\u1ee7a Data Structures and Algorithms, d\u1ecbch sang ti\u1ebfng Vi\u1ec7t l\u00e0 C\u1ea5u tr\u00fac d\u1eef li\u1ec7u v\u00e0 Thu\u1eadt to\u00e1n. \u0110\u00e2y l\u00e0 hai nh\u00e1nh ki\u1ebfn th\u1ee9c n\u1ec1n t\u1ea3ng c\u1ee7a khoa h\u1ecdc m\u00e1y t\u00ednh, nghi\u00ean c\u1ee9u c\u00e1ch t\u1ed5 ch\u1ee9c, l\u01b0u tr\u1eef d\u1eef li\u1ec7u trong b\u1ed9 nh\u1edb v\u00e0 c\u00e1ch x\u1eed l\u00fd d\u1eef li\u1ec7u \u0111\u00f3 \u0111\u1ec3 gi\u1ea3i quy\u1ebft m\u1ed9t b\u00e0i to\u00e1n c\u1ee5 th\u1ec3. Khi m\u1ed9t l\u1eadp tr\u00ecnh vi\u00ean (Software Engineer) n\u1eafm v\u1eefng DSA, h\u1ecd c\u00f3 th\u1ec3 ch\u1ecdn \u0111\u00fang c\u1ea5u tr\u00fac cho t\u1eebng b\u00e0i to\u00e1n, vi\u1ebft m\u00e3 ng\u1eafn g\u1ecdn h\u01a1n, ch\u1ea1y nhanh h\u01a1n v\u00e0 ti\u00eau t\u1ed1n \u00edt t\u00e0i nguy\u00ean h\u01a1n.<\/p>\n\n\n\n

C\u1ea5u tr\u00fac d\u1eef li\u1ec7u (Data Structures) l\u00e0 c\u00e1ch s\u1eafp x\u1ebfp d\u1eef li\u1ec7u trong b\u1ed9 nh\u1edb m\u00e1y t\u00ednh, v\u00ed d\u1ee5 nh\u01b0 m\u1ea3ng, danh s\u00e1ch li\u00ean k\u1ebft, ng\u0103n x\u1ebfp, h\u00e0ng \u0111\u1ee3i, c\u00e2y hay b\u1ea3ng b\u0103m. Thu\u1eadt to\u00e1n (Algorithms) l\u00e0 t\u1eadp h\u1ee3p c\u00e1c b\u01b0\u1edbc h\u1eefu h\u1ea1n, c\u00f3 th\u1ee9 t\u1ef1, d\u00f9ng \u0111\u1ec3 bi\u1ebfn \u0111\u1ea7u v\u00e0o th\u00e0nh \u0111\u1ea7u ra mong mu\u1ed1n, ch\u1eb3ng h\u1ea1n nh\u01b0 s\u1eafp x\u1ebfp m\u1ed9t danh s\u00e1ch, t\u00ecm ki\u1ebfm m\u1ed9t ph\u1ea7n t\u1eed hay t\u00ecm \u0111\u01b0\u1eddng \u0111i ng\u1eafn nh\u1ea5t trong \u0111\u1ed3 th\u1ecb. Hai kh\u00eda c\u1ea1nh n\u00e0y lu\u00f4n \u0111i \u0111\u00f4i v\u1edbi nhau b\u1edfi m\u1ed7i thu\u1eadt to\u00e1n \u0111\u1ec1u thao t\u00e1c tr\u00ean m\u1ed9t c\u1ea5u tr\u00fac d\u1eef li\u1ec7u c\u1ee5 th\u1ec3, v\u00e0 m\u1ed7i c\u1ea5u tr\u00fac d\u1eef li\u1ec7u ch\u1ec9 ph\u00e1t huy t\u1ed1i \u0111a gi\u00e1 tr\u1ecb khi \u0111\u01b0\u1ee3c thu\u1eadt to\u00e1n ph\u00f9 h\u1ee3p khai th\u00e1c.<\/p>\n\n\n\n

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“C\u1ea5u tr\u00fac d\u1eef li\u1ec7u th\u00f4ng minh v\u00e0 m\u00e3 ngu\u1ed3n ngu ng\u1ed1c c\u00f2n t\u1ed1t h\u01a1n nhi\u1ec1u so v\u1edbi c\u1ea5u tr\u00fac d\u1eef li\u1ec7u ngu ng\u1ed1c v\u00e0 m\u00e3 ngu\u1ed3n th\u00f4ng minh.” \u2013 \u00fd t\u01b0\u1edfng \u0111\u01b0\u1ee3c nhi\u1ec1u th\u1ebf h\u1ec7 l\u1eadp tr\u00ecnh vi\u00ean d\u1eabn l\u1ea1i t\u1eeb cu\u1ed1n The Cathedral and the Bazaar.<\/p>\n\n<\/blockquote>\n\n\n\n

2. C\u00e1c c\u1ea5u tr\u00fac d\u1eef li\u1ec7u ph\u1ed5 bi\u1ebfn trong DSA<\/h2>\n\n\n\n

H\u1ecdc DSA th\u01b0\u1eddng b\u1eaft \u0111\u1ea7u b\u1eb1ng vi\u1ec7c l\u00e0m quen v\u1edbi c\u00e1c c\u1ea5u tr\u00fac d\u1eef li\u1ec7u c\u01a1 b\u1ea3n. M\u1ed7i c\u1ea5u tr\u00fac c\u00f3 \u01b0u nh\u01b0\u1ee3c \u0111i\u1ec3m ri\u00eang v\u00e0 ph\u00f9 h\u1ee3p v\u1edbi m\u1ed9t nh\u00f3m b\u00e0i to\u00e1n c\u1ee5 th\u1ec3. Vi\u1ec7c nh\u1eadn bi\u1ebft khi n\u00e0o n\u00ean d\u00f9ng m\u1ea3ng, khi n\u00e0o n\u00ean d\u00f9ng b\u1ea3ng b\u0103m hay khi n\u00e0o c\u1ea7n \u0111\u1ebfn c\u00e2y c\u00e2n b\u1eb1ng l\u00e0 k\u1ef9 n\u0103ng ph\u00e2n bi\u1ec7t m\u1ed9t l\u1eadp tr\u00ecnh vi\u00ean c\u00f3 n\u1ec1n t\u1ea3ng v\u1eefng v\u1edbi ng\u01b0\u1eddi ch\u1ec9 bi\u1ebft vi\u1ebft m\u00e3 theo b\u1ea3n n\u0103ng. V\u1edbi nh\u1eefng b\u1ea1n \u0111ang theo \u0111u\u1ed5i \u0111\u1ecbnh h\u01b0\u1edbng ph\u00e1t tri\u1ec3n ph\u1ea7n m\u1ec1m, vi\u1ec7c th\u00e0nh th\u1ea1o nh\u00f3m c\u1ea5u tr\u00fac d\u01b0\u1edbi \u0111\u00e2y l\u00e0 \u0111i\u1ec1u ki\u1ec7n g\u1ea7n nh\u01b0 b\u1eaft bu\u1ed9c khi n\u1ed9p h\u1ed3 s\u01a1 v\u00e0o c\u00e1c v\u1ecb tr\u00ed vi\u1ec7c l\u00e0m CNTT – ph\u1ea7n m\u1ec1m<\/a><\/em><\/strong> t\u1ea1i c\u00e1c c\u00f4ng ty ph\u00e1t tri\u1ec3n s\u1ea3n ph\u1ea9m trong v\u00e0 ngo\u00e0i n\u01b0\u1edbc.<\/p>\n\n\n\n

\u2013 M\u1ea3ng (Array) l\u01b0u tr\u1eef c\u00e1c ph\u1ea7n t\u1eed c\u00f9ng ki\u1ec3u trong v\u00f9ng nh\u1edb li\u00ean ti\u1ebfp, truy c\u1eadp ng\u1eabu nhi\u00ean c\u1ef1c nhanh nh\u01b0ng ch\u00e8n x\u00f3a gi\u1eefa m\u1ea3ng t\u1ed1n chi ph\u00ed.<\/p>\n\n\n\n

\u2013 Danh s\u00e1ch li\u00ean k\u1ebft (Linked List) g\u1ed3m c\u00e1c n\u00fat n\u1ed1i v\u1edbi nhau qua con tr\u1ecf, ch\u00e8n x\u00f3a nhanh nh\u01b0ng t\u00ecm ki\u1ebfm ph\u1ea3i duy\u1ec7t tu\u1ea7n t\u1ef1.<\/p>\n\n\n\n

\u2013 Ng\u0103n x\u1ebfp (Stack) ho\u1ea1t \u0111\u1ed9ng theo nguy\u00ean t\u1eafc LIFO, d\u00f9ng nhi\u1ec1u trong g\u1ecdi h\u00e0m \u0111\u1ec7 quy v\u00e0 ph\u00e2n t\u00edch bi\u1ec3u th\u1ee9c.<\/p>\n\n\n\n

\u2013 H\u00e0ng \u0111\u1ee3i (Queue) ho\u1ea1t \u0111\u1ed9ng theo nguy\u00ean t\u1eafc FIFO, \u1ee9ng d\u1ee5ng trong l\u1eadp l\u1ecbch t\u00e1c v\u1ee5 v\u00e0 x\u1eed l\u00fd s\u1ef1 ki\u1ec7n.<\/p>\n\n\n\n

\u2013 C\u00e2y (Tree) \u0111\u1eb7c bi\u1ec7t l\u00e0 c\u00e2y nh\u1ecb ph\u00e2n t\u00ecm ki\u1ebfm v\u00e0 c\u00e2y c\u00e2n b\u1eb1ng AVL, Red-Black Tree, d\u00f9ng trong c\u01a1 s\u1edf d\u1eef li\u1ec7u v\u00e0 h\u1ec7 th\u1ed1ng t\u1ec7p.<\/p>\n\n\n\n

\u2013 B\u1ea3ng b\u0103m (Hash Table) cho ph\u00e9p tra c\u1ee9u trung b\u00ecnh trong th\u1eddi gian h\u1eb1ng s\u1ed1, l\u00e0 x\u01b0\u01a1ng s\u1ed1ng c\u1ee7a c\u1ea5u tr\u00fac dictionary trong Python hay HashMap trong Java.<\/p>\n\n\n\n

\u2013 \u0110\u1ed3 th\u1ecb (Graph) m\u00f4 h\u00ecnh h\u00f3a c\u00e1c quan h\u1ec7 ph\u1ee9c t\u1ea1p nh\u01b0 m\u1ea1ng x\u00e3 h\u1ed9i, b\u1ea3n \u0111\u1ed3 giao th\u00f4ng ho\u1eb7c m\u1ea1ng l\u01b0\u1edbi m\u00e1y ch\u1ee7.<\/p>\n\n\n\n

N\u1eafm ch\u1eafc c\u00e1c c\u1ea5u tr\u00fac tr\u00ean l\u00e0 b\u01b0\u1edbc \u0111\u1ea7u ti\u00ean \u0111\u1ec3 b\u1ea1n c\u00f3 th\u1ec3 gi\u1ea3i c\u00e1c b\u00e0i to\u00e1n th\u1ef1c t\u1ebf thay v\u00ec ch\u1ec9 h\u1ecdc v\u1eb9t t\u1eebng d\u00f2ng m\u00e3.<\/p>\n\n\n\n

3. C\u00e1c thu\u1eadt to\u00e1n ph\u1ed5 bi\u1ebfn m\u1ecdi l\u1eadp tr\u00ecnh vi\u00ean c\u1ea7n bi\u1ebft<\/h2>\n\n\n\n

Thu\u1eadt to\u00e1n l\u00e0 ph\u1ea7n linh h\u1ed3n gi\u00fap d\u1eef li\u1ec7u tr\u1edf n\u00ean c\u00f3 gi\u00e1 tr\u1ecb. N\u1ebfu b\u1ea1n \u0111ang h\u1ecdc c\u00e1c ng\u00f4n ng\u1eef ph\u1ed5 bi\u1ebfn nh\u01b0 Python hay Java, vi\u1ec7c k\u1ebft h\u1ee3p ki\u1ebfn th\u1ee9c c\u00fa ph\u00e1p v\u1edbi DSA s\u1ebd gi\u00fap b\u1ea1n vi\u1ebft m\u00e3 hi\u1ec7u qu\u1ea3 h\u01a1n r\u1ea5t nhi\u1ec1u. B\u00e0i vi\u1ebft Python l\u00e0 g\u00ec<\/a><\/em><\/strong> tr\u00ean CareerLink \u0111\u00e3 ph\u00e2n t\u00edch chi ti\u1ebft v\u00ec sao ng\u00f4n ng\u1eef n\u00e0y l\u1ea1i \u0111\u01b0\u1ee3c gi\u1edbi khoa h\u1ecdc d\u1eef li\u1ec7u \u01b0a chu\u1ed9ng, v\u00e0 m\u1ed9t ph\u1ea7n l\u00fd do ch\u00ednh l\u00e0 Python s\u1edf h\u1eefu th\u01b0 vi\u1ec7n chu\u1ea9n r\u1ea5t th\u00e2n thi\u1ec7n cho vi\u1ec7c th\u1ef1c h\u00e0nh thu\u1eadt to\u00e1n.<\/p>\n\n\n\n

\u2013 Thu\u1eadt to\u00e1n s\u1eafp x\u1ebfp g\u1ed3m Bubble Sort, Selection Sort, Insertion Sort cho ng\u01b0\u1eddi m\u1edbi v\u00e0 Merge Sort, Quick Sort, Heap Sort cho \u1ee9ng d\u1ee5ng th\u1ef1c t\u1ebf.<\/p>\n\n\n\n

\u2013 Thu\u1eadt to\u00e1n t\u00ecm ki\u1ebfm g\u1ed3m t\u00ecm ki\u1ebfm tuy\u1ebfn t\u00ednh v\u00e0 t\u00ecm ki\u1ebfm nh\u1ecb ph\u00e2n tr\u00ean m\u1ea3ng \u0111\u00e3 s\u1eafp x\u1ebfp.<\/p>\n\n\n\n

\u2013 Thu\u1eadt to\u00e1n \u0111\u1ec7 quy v\u00e0 quy ho\u1ea1ch \u0111\u1ed9ng (Dynamic Programming) gi\u1ea3i c\u00e1c b\u00e0i to\u00e1n t\u1ed1i \u01b0u nh\u01b0 d\u00e3y con chung d\u00e0i nh\u1ea5t hay b\u00e0i to\u00e1n c\u00e1i t\u00fai.<\/p>\n\n\n\n

\u2013 Thu\u1eadt to\u00e1n tham lam (Greedy) \u00e1p d\u1ee5ng cho b\u00e0i to\u00e1n ph\u1ee7 t\u1eadp h\u1ee3p, l\u1eadp l\u1ecbch ho\u1ea1t \u0111\u1ed9ng.<\/p>\n\n\n\n

\u2013 Thu\u1eadt to\u00e1n \u0111\u1ed3 th\u1ecb nh\u01b0 BFS, DFS, Dijkstra, Floyd-Warshall, Kruskal v\u00e0 Prim d\u00f9ng cho \u0111\u1ecbnh tuy\u1ebfn v\u00e0 ph\u00e2n t\u00edch m\u1ea1ng.<\/p>\n\n\n\n

\u2013 Thu\u1eadt to\u00e1n chia \u0111\u1ec3 tr\u1ecb (Divide and Conquer) l\u00e0 t\u01b0 duy n\u1ec1n cho nhi\u1ec1u gi\u1ea3i thu\u1eadt hi\u1ec7u n\u0103ng cao.<\/p>\n\n\n\n

M\u1ed7i nh\u00f3m thu\u1eadt to\u00e1n n\u00f3i tr\u00ean \u0111\u1ec1u c\u00f3 h\u00e0ng tr\u0103m b\u00e0i luy\u1ec7n tr\u00ean LeetCode, HackerRank v\u00e0 Codeforces. Vi\u1ec7c luy\u1ec7n t\u1eadp \u0111\u1ec1u \u0111\u1eb7n s\u1ebd gi\u00fap b\u1ea1n h\u00ecnh th\u00e0nh ph\u1ea3n x\u1ea1 ch\u1ecdn \u0111\u00fang c\u00e1ch ti\u1ebfp c\u1eadn khi g\u1eb7p m\u1ed9t b\u00e0i to\u00e1n m\u1edbi, thay v\u00ec l\u00fang t\u00fang kh\u00f4ng bi\u1ebft b\u1eaft \u0111\u1ea7u t\u1eeb \u0111\u00e2u.<\/p>\n\n\n\n

4. Big O Notation v\u00e0 \u0111\u1ed9 ph\u1ee9c t\u1ea1p thu\u1eadt to\u00e1n<\/h2>\n\n\n\n
\"\"<\/figure>\n\n\n\n

M\u1ed9t thu\u1eadt to\u00e1n c\u00f3 th\u1ec3 ch\u1ea1y \u0111\u00fang nh\u01b0ng v\u1eabn b\u1ecb xem l\u00e0 k\u00e9m n\u1ebfu t\u1ed1n qu\u00e1 nhi\u1ec1u th\u1eddi gian ho\u1eb7c b\u1ed9 nh\u1edb. Big O Notation l\u00e0 c\u00f4ng c\u1ee5 to\u00e1n h\u1ecdc gi\u00fap ch\u00fang ta m\u00f4 t\u1ea3 t\u1ed1c \u0111\u1ed9 t\u0103ng tr\u01b0\u1edfng c\u1ee7a th\u1eddi gian ch\u1ea1y ho\u1eb7c b\u1ed9 nh\u1edb theo k\u00edch th\u01b0\u1edbc \u0111\u1ea7u v\u00e0o n. Khi \u0111\u00e1nh gi\u00e1 m\u1ed9t gi\u1ea3i ph\u00e1p, ng\u01b0\u1eddi ph\u1ecfng v\u1ea5n \u1edf c\u00e1c c\u00f4ng ty FAANG th\u01b0\u1eddng h\u1ecfi c\u1ea3 \u0111\u1ed9 ph\u1ee9c t\u1ea1p th\u1eddi gian (time complexity) l\u1eabn \u0111\u1ed9 ph\u1ee9c t\u1ea1p kh\u00f4ng gian (space complexity), b\u1edfi \u0111\u00e2y l\u00e0 hai ch\u1ec9 s\u1ed1 ph\u1ea3n \u00e1nh tr\u1ef1c ti\u1ebfp kh\u1ea3 n\u0103ng v\u1eadn h\u00e0nh c\u1ee7a \u1ee9ng d\u1ee5ng khi d\u1eef li\u1ec7u m\u1edf r\u1ed9ng l\u00ean h\u00e0ng tri\u1ec7u b\u1ea3n ghi.<\/p>\n\n\n\n

C\u00e1c m\u1ee9c \u0111\u1ed9 ph\u1ee9c t\u1ea1p th\u01b0\u1eddng g\u1eb7p x\u1ebfp theo th\u1ee9 t\u1ef1 t\u1eeb t\u1ed1t \u0111\u1ebfn x\u1ea5u g\u1ed3m O(1), O(log n), O(n), O(n log n), O(n\u00b2), O(2\u207f) v\u00e0 O(n!). M\u1ed9t thu\u1eadt to\u00e1n O(log n) nh\u01b0 t\u00ecm ki\u1ebfm nh\u1ecb ph\u00e2n c\u00f3 th\u1ec3 x\u1eed l\u00fd m\u1ed9t t\u1ef7 ph\u1ea7n t\u1eed ch\u1ec9 trong kho\u1ea3ng ba m\u01b0\u01a1i b\u01b0\u1edbc, trong khi m\u1ed9t thu\u1eadt to\u00e1n O(n\u00b2) s\u1ebd tr\u1edf n\u00ean kh\u00f4ng th\u1ec3 ch\u1ea5p nh\u1eadn khi n v\u01b0\u1ee3t qu\u00e1 v\u00e0i ch\u1ee5c ngh\u00ecn. Hi\u1ec3u Big O gi\u00fap l\u1eadp tr\u00ecnh vi\u00ean d\u1ef1 \u0111o\u00e1n hi\u1ec7u n\u0103ng tr\u01b0\u1edbc khi vi\u1ebft m\u00e3, thay v\u00ec ph\u1ea3i \u0111o \u0111\u1ea1c l\u1ea1i sau khi s\u1ea3n ph\u1ea9m g\u1eb7p s\u1ef1 c\u1ed1.<\/p>\n\n\n\n

C\u1ea5u tr\u00fac d\u1eef li\u1ec7u<\/th>Truy c\u1eadp<\/th>T\u00ecm ki\u1ebfm<\/th>Ch\u00e8n<\/th>X\u00f3a<\/th>\u1ee8ng d\u1ee5ng ti\u00eau bi\u1ec3u<\/th><\/tr><\/thead>
Array<\/td>O(1)<\/td>O(n)<\/td>O(n)<\/td>O(n)<\/td>L\u01b0u danh s\u00e1ch c\u1ed1 \u0111\u1ecbnh<\/td><\/tr>
Linked List<\/td>O(n)<\/td>O(n)<\/td>O(1)<\/td>O(1)<\/td>H\u00e0ng \u0111\u1ee3i t\u00e1c v\u1ee5 \u0111\u1ed9ng<\/td><\/tr>
Stack<\/td>O(n)<\/td>O(n)<\/td>O(1)<\/td>O(1)<\/td>\u0110\u1ec7 quy, undo\/redo<\/td><\/tr>
Queue<\/td>O(n)<\/td>O(n)<\/td>O(1)<\/td>O(1)<\/td>L\u1eadp l\u1ecbch t\u00e1c v\u1ee5<\/td><\/tr>
Binary Search Tree<\/td>O(log n)<\/td>O(log n)<\/td>O(log n)<\/td>O(log n)<\/td>Ch\u1ec9 m\u1ee5c c\u01a1 s\u1edf d\u1eef li\u1ec7u<\/td><\/tr>
Hash Table<\/td>N\/A<\/td>O(1)<\/td>O(1)<\/td>O(1)<\/td>Cache, t\u1eeb \u0111i\u1ec3n<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
\n

\u2013 L\u01b0u \u00fd: c\u00e1c gi\u00e1 tr\u1ecb Big O trong b\u1ea3ng l\u00e0 \u0111\u1ed9 ph\u1ee9c t\u1ea1p trung b\u00ecnh. Tr\u01b0\u1eddng h\u1ee3p x\u1ea5u nh\u1ea5t c\u1ee7a Hash Table c\u00f3 th\u1ec3 l\u00ean O(n) khi x\u1ea3y ra xung \u0111\u1ed9t b\u0103m.<\/p>\n

\u2013 C\u00e2y nh\u1ecb ph\u00e2n t\u00ecm ki\u1ebfm ch\u1ec9 gi\u1eef \u0111\u01b0\u1ee3c O(log n) khi c\u00e2y c\u00e2n b\u1eb1ng, v\u00ec v\u1eady th\u1ef1c t\u1ebf th\u01b0\u1eddng d\u00f9ng AVL ho\u1eb7c Red-Black Tree.<\/p>\n<\/div>\n\n\n\n

5. T\u1ea1i sao DSA quan tr\u1ecdng v\u00e0 l\u1ed9 tr\u00ecnh h\u1ecdc DSA b\u00e0i b\u1ea3n<\/h2>\n\n\n\n

Nhi\u1ec1u b\u1ea1n m\u1edbi h\u1ecdc l\u1eadp tr\u00ecnh th\u01b0\u1eddng \u0111\u1eb7t c\u00e2u h\u1ecfi li\u1ec7u c\u00f3 c\u1ea7n h\u1ecdc DSA hay kh\u00f4ng khi c\u00f4ng vi\u1ec7c th\u1ef1c t\u1ebf ch\u1ee7 y\u1ebfu l\u00e0 x\u00e2y d\u1ef1ng giao di\u1ec7n v\u00e0 g\u1ecdi API. C\u00e2u tr\u1ea3 l\u1eddi l\u00e0 DSA kh\u00f4ng tr\u1ef1c ti\u1ebfp xu\u1ea5t hi\u1ec7n trong t\u1eebng d\u00f2ng m\u00e3 h\u1eb1ng ng\u00e0y, nh\u01b0ng n\u00f3 \u0111\u1ecbnh h\u00ecnh c\u00e1ch b\u1ea1n t\u01b0 duy v\u1ec1 v\u1ea5n \u0111\u1ec1. M\u1ed9t ng\u01b0\u1eddi hi\u1ec3u DSA s\u1ebd bi\u1ebft khi n\u00e0o n\u00ean d\u00f9ng HashMap thay v\u00ec duy\u1ec7t m\u1ea3ng, khi n\u00e0o n\u00ean \u0111\u00e1nh ch\u1ec9 m\u1ee5c cho c\u01a1 s\u1edf d\u1eef li\u1ec7u, hay khi n\u00e0o m\u1ed9t v\u00f2ng l\u1eb7p l\u1ed3ng nhau s\u1ebd tr\u1edf th\u00e0nh th\u1ea3m h\u1ecda hi\u1ec7u n\u0103ng. \u0110\u00e2y c\u0169ng l\u00e0 l\u00fd do c\u00e1c k\u1ef3 thi nh\u01b0 ACM ICPC, Google Code Jam hay v\u00f2ng ph\u1ecfng v\u1ea5n c\u1ee7a c\u00e1c t\u1eadp \u0111o\u00e0n FAANG \u0111\u1ec1u xoay quanh DSA.<\/p>\n\n\n\n

L\u1ed9 tr\u00ecnh h\u1ecdc DSA h\u1ee3p l\u00fd n\u00ean b\u1eaft \u0111\u1ea7u t\u1eeb c\u00e1c kh\u00e1i ni\u1ec7m c\u01a1 b\u1ea3n v\u1ec1 \u0111\u1ed9 ph\u1ee9c t\u1ea1p, sau \u0111\u00f3 \u0111\u1ebfn c\u1ea5u tr\u00fac d\u1eef li\u1ec7u tuy\u1ebfn t\u00ednh, c\u1ea5u tr\u00fac d\u1eef li\u1ec7u phi tuy\u1ebfn v\u00e0 cu\u1ed1i c\u00f9ng l\u00e0 c\u00e1c k\u1ef9 thu\u1eadt gi\u1ea3i thu\u1eadt n\u00e2ng cao. T\u00e0i li\u1ec7u kinh \u0111i\u1ec3n nh\u1ea5t cho ng\u01b0\u1eddi h\u1ecdc nghi\u00eam t\u00fac l\u00e0 cu\u1ed1n Introduction to Algorithms (CLRS) c\u1ee7a b\u1ed1n t\u00e1c gi\u1ea3 Cormen, Leiserson, Rivest v\u00e0 Stein, c\u00f9ng v\u1edbi b\u1ed9 The Art of Computer Programming c\u1ee7a Donald Knuth. Song song v\u1edbi vi\u1ec7c \u0111\u1ecdc l\u00fd thuy\u1ebft, b\u1ea1n n\u00ean luy\u1ec7n t\u1eadp tr\u00ean LeetCode m\u1ed7i ng\u00e0y, b\u1eaft \u0111\u1ea7u t\u1eeb c\u00e1c b\u00e0i Easy r\u1ed3i n\u00e2ng d\u1ea7n l\u00ean Medium v\u00e0 Hard.<\/p>\n\n\n\n

\n

\u2013 L\u1eddi khuy\u00ean: d\u00e0nh \u00edt nh\u1ea5t ba m\u01b0\u01a1i ph\u00fat m\u1ed7i ng\u00e0y luy\u1ec7n m\u1ed9t b\u00e0i LeetCode, sau khi gi\u1ea3i xong h\u00e3y \u0111\u1ecdc l\u1eddi gi\u1ea3i t\u1ed1i \u01b0u \u0111\u1ec3 h\u1ecdc c\u00e1ch t\u01b0 duy m\u1edbi.<\/p>\n

\u2013 Ghi ch\u00fa l\u1ea1i c\u00e1c pattern th\u01b0\u1eddng g\u1eb7p nh\u01b0 sliding window, two pointers, prefix sum, monotonic stack \u0111\u1ec3 \u00e1p d\u1ee5ng nhanh khi g\u1eb7p b\u00e0i t\u01b0\u01a1ng t\u1ef1.<\/p>\n

\u2013 Tham gia c\u00e1c k\u1ef3 thi h\u1eb1ng tu\u1ea7n tr\u00ean Codeforces gi\u00fap r\u00e8n ph\u1ea3n x\u1ea1 gi\u1ea3i b\u00e0i d\u01b0\u1edbi \u00e1p l\u1ef1c th\u1eddi gian.<\/p>\n<\/div>\n\n\n\n

M\u1ed9t l\u1ed9 tr\u00ecnh tham kh\u1ea3o k\u00e9o d\u00e0i kho\u1ea3ng s\u00e1u th\u00e1ng c\u00f3 th\u1ec3 chia th\u00e0nh ba giai \u0111o\u1ea1n. Giai \u0111o\u1ea1n \u0111\u1ea7u hai th\u00e1ng t\u1eadp trung v\u00e0o m\u1ea3ng, chu\u1ed7i, danh s\u00e1ch li\u00ean k\u1ebft, ng\u0103n x\u1ebfp, h\u00e0ng \u0111\u1ee3i v\u00e0 \u0111\u1ec7 quy. Giai \u0111o\u1ea1n hai th\u00e1ng ti\u1ebfp theo \u0111i s\u00e2u v\u00e0o c\u00e2y, \u0111\u1ed3 th\u1ecb, s\u1eafp x\u1ebfp, t\u00ecm ki\u1ebfm v\u00e0 b\u1ea3ng b\u0103m. Giai \u0111o\u1ea1n cu\u1ed1i hai th\u00e1ng d\u00e0nh cho quy ho\u1ea1ch \u0111\u1ed9ng, thu\u1eadt to\u00e1n tham lam, backtracking v\u00e0 c\u00e1c b\u00e0i to\u00e1n n\u00e2ng cao tr\u00ean \u0111\u1ed3 th\u1ecb. Khi ho\u00e0n t\u1ea5t s\u00e1u th\u00e1ng n\u00e0y, b\u1ea1n \u0111\u00e3 \u0111\u1ee7 t\u1ef1 tin \u0111\u1ec3 b\u01b0\u1edbc v\u00e0o c\u00e1c v\u00f2ng ph\u1ecfng v\u1ea5n thu\u1eadt to\u00e1n \u1edf m\u1ee9c trung c\u1ea5p.<\/p>\n\n\n\n

6. Th\u1ecb tr\u01b0\u1eddng ngh\u1ec1 DSA trong l\u1eadp tr\u00ecnh tr\u00ean CareerLink (2026)<\/h2>\n\n\n\n

D\u01b0\u1edbi \u0111\u00e2y l\u00e0 b\u1ee9c tranh t\u1ed5ng quan th\u1ecb tr\u01b0\u1eddng tuy\u1ec3n d\u1ee5ng v\u1ecb tr\u00ed dsa trong l\u1eadp tr\u00ecnh d\u1ef1a tr\u00ean d\u1eef li\u1ec7u c\u1eadp nh\u1eadt t\u1eeb CareerLink n\u0103m 2026. S\u1ed1 li\u1ec7u ph\u1ea3n \u00e1nh tin \u0111\u0103ng th\u1ef1c t\u1ebf v\u00e0 l\u00e0 tham chi\u1ebfu h\u1eefu \u00edch cho \u1ee9ng vi\u00ean \u0111\u1ecbnh h\u01b0\u1edbng ngh\u1ec1 nghi\u1ec7p.<\/p>\n\n\n\n\n\n\n
Ch\u1ec9 s\u1ed1<\/th>D\u1eef li\u1ec7u CareerLink 2026<\/th><\/tr>\n<\/thead>\n
T\u1ed5ng s\u1ed1 tin tuy\u1ec3n d\u1ee5ng \u0111ang m\u1edf<\/strong><\/td>428 tin tuy\u1ec3n d\u1ee5ng \u0111ang m\u1edf tr\u00ean CareerLink 2026<\/td><\/tr>\n
M\u1ee9c l\u01b0\u01a1ng tham chi\u1ebfu theo c\u1ea5p b\u1eadc<\/strong><\/td>Trung b\u00ecnh 10 \u2013 30 tri\u1ec7u\/th\u00e1ng (theo c\u1ea5p: IT junior 15\u201325 tri\u1ec7u | Senior 30\u201350 tri\u1ec7u | Lead\/Architect 50\u201380 tri\u1ec7u\/th\u00e1ng (network\/security))<\/td><\/tr>\n
Top v\u1ecb tr\u00ed c\u1ee5 th\u1ec3 \u0111\u01b0\u1ee3c tuy\u1ec3n nhi\u1ec1u<\/strong><\/td>\u0110a d\u1ea1ng v\u1ecb tr\u00ed t\u1eeb junior \u0111\u1ebfn senior \u2014 xem tin \u0111\u0103ng c\u1ee5 th\u1ec3 trong chuy\u00ean m\u1ee5c t\u01b0\u01a1ng \u1ee9ng<\/td><\/tr>\n
Khu v\u1ef1c tuy\u1ec3n d\u1ee5ng t\u1eadp trung<\/strong><\/td>TP.HCM, H\u00e0 N\u1ed9i, \u0110\u00e0 N\u1eb5ng<\/td><\/tr>\n
Doanh nghi\u1ec7p \u0111\u0103ng tuy\u1ec3n ti\u00eau bi\u1ec3u<\/strong><\/td>\u0110a d\u1ea1ng doanh nghi\u1ec7p FDI v\u00e0 n\u1ed9i \u0111\u1ecba<\/td><\/tr>\n
K\u1ef9 n\u0103ng v\u00e0 ch\u1ee9ng ch\u1ec9 \u0111\u01b0\u1ee3c \u01b0u ti\u00ean<\/strong><\/td>Cisco CCNA\/CCNP cho m\u1ea1ng | Cloud AWS\/GCP\/Azure | B\u1ea3o m\u1eadt ISO 27001 \/ NIST | Linux administration | Python automation script<\/td><\/tr>\n
Xu h\u01b0\u1edbng tuy\u1ec3n d\u1ee5ng 2026<\/strong><\/td>Cybersecurity v\u00e0 Network Security \u0111ang l\u00e0 nh\u00f3m c\u00f3 c\u1ea7u l\u1edbn nh\u1ea5t ng\u00e0nh CNTT. Ch\u1ee9ng ch\u1ec9 CEH\/CCNA\/CCNP t\u0103ng l\u01b0\u01a1ng 25\u201335%.<\/td><\/tr>\n<\/tbody>\n<\/table>\n\n\n\n
\n

G\u1ee3i \u00fd t\u1eeb d\u1eef li\u1ec7u CareerLink 2026<\/strong><\/p>\n

\u2013 \u1ee8ng vi\u00ean n\u00ean \u0111\u1ed1i chi\u1ebfu k\u1ef9 n\u0103ng v\u00e0 ch\u1ee9ng ch\u1ec9 c\u00e1 nh\u00e2n v\u1edbi y\u00eau c\u1ea7u th\u1ef1c t\u1ebf trong tin \u0111\u0103ng m\u1edbi nh\u1ea5t t\u1ea1i chuy\u00ean m\u1ee5c t\u01b0\u01a1ng \u1ee9ng.<\/p>\n

\u2013 M\u1ee9c l\u01b0\u01a1ng tr\u00ean l\u00e0 d\u1ea3i tham chi\u1ebfu \u2014 thu nh\u1eadp th\u1ef1c t\u1ebf ph\u1ee5 thu\u1ed9c quy m\u00f4 doanh nghi\u1ec7p, v\u1ecb tr\u00ed \u0111\u1ecba l\u00fd v\u00e0 kinh nghi\u1ec7m c\u1ee5 th\u1ec3.<\/p>\n

\u2013 \u0110\u1ea7u t\u01b0 ch\u1ee9ng ch\u1ec9 chuy\u00ean ng\u00e0nh v\u00e0 ngo\u1ea1i ng\u1eef l\u00e0 c\u00e1ch hi\u1ec7u qu\u1ea3 nh\u1ea5t \u0111\u1ec3 v\u01b0\u1ee3t l\u00ean trung v\u1ecb l\u01b0\u01a1ng.<\/p>\n<\/div>\n\n\n\n

7. C\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p<\/h2>\n\n\n\n

1. H\u1ecdc DSA c\u00f3 c\u1ea7n gi\u1ecfi to\u00e1n kh\u00f4ng?<\/em><\/strong><\/p>\n\n\n\n

B\u1ea1n kh\u00f4ng c\u1ea7n gi\u1ecfi to\u00e1n cao c\u1ea5p, nh\u01b0ng c\u1ea7n n\u1eafm v\u1eefng to\u00e1n r\u1eddi r\u1ea1c c\u01a1 b\u1ea3n nh\u01b0 t\u1ed5 h\u1ee3p, x\u00e1c su\u1ea5t, logic m\u1ec7nh \u0111\u1ec1 v\u00e0 quy n\u1ea1p. T\u01b0 duy logic m\u1edbi l\u00e0 y\u1ebfu t\u1ed1 quy\u1ebft \u0111\u1ecbnh, kh\u00f4ng ph\u1ea3i vi\u1ec7c t\u00ednh to\u00e1n ph\u1ee9c t\u1ea1p.<\/p>\n\n\n\n

2. N\u00ean h\u1ecdc DSA b\u1eb1ng ng\u00f4n ng\u1eef n\u00e0o?<\/em><\/strong><\/p>\n\n\n\n

Python ph\u00f9 h\u1ee3p cho ng\u01b0\u1eddi m\u1edbi v\u00ec c\u00fa ph\u00e1p ng\u1eafn g\u1ecdn, trong khi C++ v\u00e0 Java \u0111\u01b0\u1ee3c \u01b0a chu\u1ed9ng trong c\u00e1c k\u1ef3 thi nh\u1edd hi\u1ec7u n\u0103ng cao v\u00e0 b\u1ed9 th\u01b0 vi\u1ec7n chu\u1ea9n m\u1ea1nh. B\u1ea1n n\u00ean ch\u1ecdn ng\u00f4n ng\u1eef m\u00ecnh tho\u1ea3i m\u00e1i nh\u1ea5t \u0111\u1ec3 t\u1eadp trung v\u00e0o t\u01b0 duy gi\u1ea3i thu\u1eadt.<\/p>\n\n\n\n

3. M\u1ea5t bao l\u00e2u \u0111\u1ec3 th\u00e0nh th\u1ea1o DSA?<\/em><\/strong><\/p>\n\n\n\n

V\u1edbi ng\u01b0\u1eddi luy\u1ec7n t\u1eadp \u0111\u1ec1u \u0111\u1eb7n m\u1ed7i ng\u00e0y, s\u00e1u \u0111\u1ebfn m\u01b0\u1eddi hai th\u00e1ng l\u00e0 kho\u1ea3ng th\u1eddi gian h\u1ee3p l\u00fd \u0111\u1ec3 n\u1eafm ch\u1eafc c\u00e1c pattern c\u01a1 b\u1ea3n v\u00e0 gi\u1ea3i t\u1ed1t c\u00e1c b\u00e0i Medium tr\u00ean LeetCode. M\u1ee9c Hard v\u00e0 c\u00e1c b\u00e0i thi Codeforces div 1 c\u1ea7n th\u00eam nhi\u1ec1u n\u0103m t\u00edch l\u0169y.<\/p>\n\n\n\n

T\u00f3m l\u1ea1i, DSA l\u00e0 g\u00ec trong l\u1eadp tr\u00ecnh<\/strong> kh\u00f4ng ch\u1ec9 \u0111\u01a1n thu\u1ea7n l\u00e0 m\u1ed9t c\u00e2u h\u1ecfi l\u00fd thuy\u1ebft m\u00e0 c\u00f2n l\u00e0 c\u00e1nh c\u1eeda d\u1eabn v\u00e0o t\u01b0 duy gi\u1ea3i quy\u1ebft v\u1ea5n \u0111\u1ec1 b\u00e0i b\u1ea3n c\u1ee7a ng\u00e0nh khoa h\u1ecdc m\u00e1y t\u00ednh. Khi b\u1ea1n n\u1eafm v\u1eefng c\u1ea5u tr\u00fac d\u1eef li\u1ec7u, thu\u1eadt to\u00e1n v\u00e0 bi\u1ebft c\u00e1ch ph\u00e2n t\u00edch \u0111\u1ed9 ph\u1ee9c t\u1ea1p Big O, m\u1ed7i d\u00f2ng m\u00e3 vi\u1ebft ra \u0111\u1ec1u c\u00f3 c\u01a1 s\u1edf khoa h\u1ecdc r\u00f5 r\u00e0ng. H\u00e0nh tr\u00ecnh h\u1ecdc DSA \u0111\u00f2i h\u1ecfi ki\u00ean tr\u00ec v\u00e0 th\u1ef1c h\u00e0nh li\u00ean t\u1ee5c, nh\u01b0ng ph\u1ea7n th\u01b0\u1edfng nh\u1eadn l\u1ea1i s\u1ebd l\u00e0 n\u1ec1n t\u1ea3ng v\u1eefng ch\u1eafc cho c\u1ea3 s\u1ef1 nghi\u1ec7p l\u1eadp tr\u00ecnh l\u00e2u d\u00e0i.<\/p>\n\n\n\n

Minh An<\/strong><\/p>\n\n\n\n

B\u00e0i vi\u1ebft mang t\u00ednh ch\u1ea5t tham kh\u1ea3o, c\u00e1c th\u00f4ng tin v\u1ec1 c\u1ea5u tr\u00fac d\u1eef li\u1ec7u, thu\u1eadt to\u00e1n v\u00e0 \u0111\u1ed9 ph\u1ee9c t\u1ea1p c\u00f3 th\u1ec3 thay \u0111\u1ed5i theo t\u1eebng phi\u00ean b\u1ea3n ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh. Ng\u01b0\u1eddi \u0111\u1ecdc n\u00ean \u0111\u1ed1i chi\u1ebfu th\u00eam v\u1edbi t\u00e0i li\u1ec7u ch\u00ednh th\u1ee9c c\u1ee7a ng\u00f4n ng\u1eef m\u00ecnh s\u1eed d\u1ee5ng tr\u01b0\u1edbc khi \u00e1p d\u1ee5ng v\u00e0o d\u1ef1 \u00e1n th\u1ef1c t\u1ebf.<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

DSA l\u00e0 g\u00ec trong l\u1eadp tr\u00ecnh? T\u00ecm hi\u1ec3u c\u1ea5u tr\u00fac d\u1eef li\u1ec7u, thu\u1eadt to\u00e1n, \u0111\u1ed9 ph\u1ee9c t\u1ea1p Big O v\u00e0 l\u1ed9 tr\u00ecnh h\u1ecdc DSA b\u00e0i b\u1ea3n cho l\u1eadp tr\u00ecnh vi\u00ean mu\u1ed1n ti\u1ebfn xa.<\/p>\n","protected":false},"author":58,"featured_media":16478,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[17],"tags":[98],"class_list":["post-16400","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-tu-van-nghe-nghiep","tag-kien-thuc-nganh"],"_links":{"self":[{"href":"https:\/\/mb668s.com\/cam-nang-7mb66-xoc-dia\/wp-json\/wp\/v2\/posts\/16400","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mb668s.com\/cam-nang-7mb66-xoc-dia\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mb668s.com\/cam-nang-7mb66-xoc-dia\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mb668s.com\/cam-nang-7mb66-xoc-dia\/wp-json\/wp\/v2\/users\/58"}],"replies":[{"embeddable":true,"href":"https:\/\/mb668s.com\/cam-nang-7mb66-xoc-dia\/wp-json\/wp\/v2\/comments?post=16400"}],"version-history":[{"count":7,"href":"https:\/\/mb668s.com\/cam-nang-7mb66-xoc-dia\/wp-json\/wp\/v2\/posts\/16400\/revisions"}],"predecessor-version":[{"id":20945,"href":"https:\/\/mb668s.com\/cam-nang-7mb66-xoc-dia\/wp-json\/wp\/v2\/posts\/16400\/revisions\/20945"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/mb668s.com\/cam-nang-7mb66-xoc-dia\/wp-json\/wp\/v2\/media\/16478"}],"wp:attachment":[{"href":"https:\/\/mb668s.com\/cam-nang-7mb66-xoc-dia\/wp-json\/wp\/v2\/media?parent=16400"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mb668s.com\/cam-nang-7mb66-xoc-dia\/wp-json\/wp\/v2\/categories?post=16400"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mb668s.com\/cam-nang-7mb66-xoc-dia\/wp-json\/wp\/v2\/tags?post=16400"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}