{"id":114110,"date":"2026-10-08T11:09:04","date_gmt":"2026-10-08T03:09:04","guid":{"rendered":"https:\/\/www.wsisp.com\/helps\/114110.html"},"modified":"2026-10-08T11:09:04","modified_gmt":"2026-10-08T03:09:04","slug":"%e3%80%90%e5%8a%a8%e6%80%81%e8%a7%84%e5%88%92-2%e3%80%915-%e6%9c%80%e9%95%bf%e5%9b%9e%e6%96%87%e5%ad%90%e4%b8%b2","status":"publish","type":"post","link":"https:\/\/www.wsisp.com\/helps\/114110.html","title":{"rendered":"\u3010\u52a8\u6001\u89c4\u5212-2\u30115.\u6700\u957f\u56de\u6587\u5b50\u4e32"},"content":{"rendered":"

\u9898\u76ee\u63cf\u8ff0：<\/h2>\n

\u7ed9\u4f60\u4e00\u4e2a\u5b57\u7b26\u4e32 s，\u627e\u5230 s \u4e2d\u6700\u957f\u7684\u56de\u6587\u5b50\u4e32\u3002<\/p>\n

\u5982\u679c\u5b57\u7b26\u4e32\u5411\u524d\u548c\u5411\u540e\u8bfb\u90fd\u76f8\u540c，\u5219\u5b83\u6ee1\u8db3 \u56de\u6587\u6027\u3002<\/p>\n

\u5b50\u5b57\u7b26\u4e32 \u662f\u5b57\u7b26\u4e32\u4e2d\u8fde\u7eed\u7684 \u975e\u7a7a \u5b57\u7b26\u5e8f\u5217\u3002<\/p>\n

\u00a0<\/p>\n

\u793a\u4f8b 1：<\/p>\n

\u8f93\u5165：s = "babad"
\n\u8f93\u51fa："bab"
\n\u89e3\u91ca："aba" \u540c\u6837\u662f\u7b26\u5408\u9898\u610f\u7684\u7b54\u6848\u3002<\/p>\n

\u793a\u4f8b 2：<\/p>\n

\u8f93\u5165：s = "cbbd"
\n\u8f93\u51fa："bb"<\/p>\n

\u89e3\u9898\u601d\u8def<\/span>：<\/h2>\n

\u65b9\u6cd5\u4e00：\u4e2d\u5fc3\u6269\u5c55\u6cd5(\u6700\u4f18\u89e3)<\/h3>\n

\u6838\u5fc3\u601d\u8def：<\/h4>\n

\u56de\u6587\u4e32\u4e00\u5b9a\u6709\u4e00\u4e2a\u4e2d\u5fc3：<\/p>\n

    \n
  • \n

    \u5947\u6570\u957f\u5ea6：\u4e2d\u5fc3\u662f\u4e00\u4e2a\u5b57\u7b26（\u5982 "aba" \u4e2d\u5fc3\u662f b）<\/p>\n<\/li>\n

  • \n

    \u5076\u6570\u957f\u5ea6：\u4e2d\u5fc3\u662f\u4e24\u4e2a\u5b57\u7b26\u4e4b\u95f4（\u5982 "abba" \u4e2d\u5fc3\u662f bb \u4e4b\u95f4）<\/p>\n<\/li>\n<\/ul>\n

    \u4ece\u6bcf\u4e2a\u4e2d\u5fc3\u5411\u4e24\u8fb9\u6269\u5c55，\u627e\u5230\u6700\u957f\u7684\u56de\u6587\u3002<\/p>\n

    \u5177\u4f53\u8fc7\u7a0b\u793a\u4f8b：<\/h4>\n

    s = "babad"<\/p>\n

    \u4e2d\u5fc3 i=0 ('b'): \u6269\u5c55 \u2192 "b"
    \n\u4e2d\u5fc3 i=1 ('a'): \u6269\u5c55 \u2192 "bab"
    \n\u4e2d\u5fc3 i=2 ('b'): \u6269\u5c55 \u2192 "aba"
    \n\u4e2d\u5fc3 i=3 ('a'): \u6269\u5c55 \u2192 "a"
    \n\u4e2d\u5fc3 i=4 ('d'): \u6269\u5c55 \u2192 "d"<\/p>\n

    \u5076\u6570\u4e2d\u5fc3:
    \n\u4e2d\u5fc3 i=0.5: \u6269\u5c55 \u2192 ""
    \n\u4e2d\u5fc3 i=1.5: \u6269\u5c55 \u2192 ""
    \n…<\/p>\n

    \u6700\u957f: "bab" \u6216 "aba" \u2705<\/p>\n

    \u4ee3\u7801\u5b9e\u73b0：<\/h4>\n

    class Solution {
    \npublic:
    \n string longestPalindrome(string s) {
    \n if (s.empty()) return "";<\/p>\n

    int start = 0, maxLen = 1;<\/p>\n

    for (int i = 0; i < s.size(); i++) {
    \n \/\/ \u5947\u6570\u957f\u5ea6\u56de\u6587，\u4e2d\u5fc3\u662f s[i]
    \n int len1 = expandAroundCenter(s, i, i);
    \n \/\/ \u5076\u6570\u957f\u5ea6\u56de\u6587，\u4e2d\u5fc3\u662f s[i] \u548c s[i+1] \u4e4b\u95f4
    \n int len2 = expandAroundCenter(s, i, i + 1);<\/p>\n

    int len = max(len1, len2);
    \n if (len > maxLen) {
    \n maxLen = len;
    \n start = i – (len – 1) \/ 2;
    \n }
    \n }<\/p>\n

    return s.substr(start, maxLen);
    \n }<\/p>\n

    private:
    \n int expandAroundCenter(string& s, int left, int right) {
    \n while (left >= 0 && right < s.size() && s[left] == s[right]) {
    \n left–;
    \n right++;
    \n }
    \n return right – left – 1; \/\/ \u56de\u6587\u957f\u5ea6
    \n }
    \n};<\/p>\n

    \u590d\u6742\u5ea6\u5206\u6790<\/h4>\n\n\u7ef4\u5ea6\u590d\u6742\u5ea6\u8bf4\u660e<\/tr>\n\n\n\n
    \u65f6\u95f4\u590d\u6742\u5ea6<\/td>\nO(n\u00b2)<\/td>\n\u6bcf\u4e2a\u4e2d\u5fc3\u6269\u5c55 O(n)，\u5171 n \u4e2a\u4e2d\u5fc3<\/td>\n<\/tr>\n
    \u7a7a\u95f4\u590d\u6742\u5ea6<\/td>\nO(1)<\/td>\n\u53ea\u7528\u5e38\u6570\u4e2a\u53d8\u91cf<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

    \u65b9\u6cd5\u4e8c：\u52a8\u6001\u89c4\u5212<\/h3>\n

    \u601d\u8def：<\/h4>\n

    dp[i][j] \u8868\u793a s[i..j] \u662f\u5426\u662f\u56de\u6587\u3002<\/p>\n

      \n
    • \n

      s[i] == s[j] \u4e14 dp[i+1][j-1] \u4e3a\u771f \u2192 dp[i][j] \u4e3a\u771f<\/p>\n<\/li>\n

    • \n

      \u8fb9\u754c：j – i <= 1 \u65f6，\u53ea\u8981 s[i] == s[j] \u5c31\u662f\u56de\u6587<\/p>\n<\/li>\n<\/ul>\n

      \u4ee3\u7801\u5b9e\u73b0：<\/h4>\n

      class Solution {
      \npublic:
      \n string longestPalindrome(string s) {
      \n int n = s.size();
      \n if (n < 2) return s;<\/p>\n

      vector<vector<bool>> dp(n, vector<bool>(n, false));
      \n int start = 0, maxLen = 1;<\/p>\n

      \/\/ \u521d\u59cb\u5316：\u5355\u4e2a\u5b57\u7b26\u90fd\u662f\u56de\u6587
      \n for (int i = 0; i < n; i++) {
      \n dp[i][i] = true;
      \n }<\/p>\n

      \/\/ \u6309\u957f\u5ea6\u9012\u589e\u904d\u5386
      \n for (int len = 2; len <= n; len++) {
      \n for (int i = 0; i + len – 1 < n; i++) {
      \n int j = i + len – 1;<\/p>\n

      if (s[i] == s[j]) {
      \n if (len == 2 || dp[i+1][j-1]) {
      \n dp[i][j] = true;
      \n if (len > maxLen) {
      \n maxLen = len;
      \n start = i;
      \n }
      \n }
      \n }
      \n }
      \n }<\/p>\n

      return s.substr(start, maxLen);
      \n }
      \n};<\/p>\n

      \u590d\u6742\u5ea6：\u65f6\u95f4 O(n\u00b2)，\u7a7a\u95f4 O(n\u00b2)<\/p>\n

      \u65b9\u6cd5\u4e09：Manacher \u7b97\u6cd5<\/h3>\n

      \u6838\u5fc3\u601d\u8def：<\/h4>\n

      \u7b2c\u4e00\u6b65：\u9884\u5904\u7406，\u7edf\u4e00\u5947\u5076<\/p>\n

      \u56de\u6587\u6709\u4e24\u79cd：<\/p>\n

        \n
      • \n

        \u5947\u6570\u957f\u5ea6："aba"，\u4e2d\u5fc3\u662f\u5355\u4e2a\u5b57\u7b26<\/p>\n<\/li>\n

      • \n

        \u5076\u6570\u957f\u5ea6："abba"，\u4e2d\u5fc3\u662f\u4e24\u4e2a\u5b57\u7b26\u4e4b\u95f4<\/p>\n<\/li>\n<\/ul>\n

        Manacher \u7684\u505a\u6cd5\u662f\u63d2\u5165\u7279\u6b8a\u5b57\u7b26，\u628a\u6240\u6709\u56de\u6587\u90fd\u53d8\u6210\u5947\u6570\u957f\u5ea6\u3002<\/p>\n

        \u63d2\u5165 #：<\/p>\n

        \u539f\u4e32: a b a
        \n\u65b0\u4e32: # a # b # a #<\/p>\n

        \u539f\u4e32: a b b a
        \n\u65b0\u4e32: # a # b # b # a #<\/p>\n

        \u6548\u679c：<\/p>\n

          \n
        • \n

          \u539f\u6765\u5947\u6570\u957f\u5ea6 "aba"（\u957f\u5ea63）\u2192 \u65b0\u4e32 "#a#b#a#"（\u957f\u5ea67），\u4e2d\u5fc3\u662f b<\/p>\n<\/li>\n

        • \n

          \u539f\u6765\u5076\u6570\u957f\u5ea6 "abba"（\u957f\u5ea64）\u2192 \u65b0\u4e32 "#a#b#b#a#"（\u957f\u5ea69），\u4e2d\u5fc3\u662f #<\/p>\n<\/li>\n<\/ul>\n

          \u6240\u6709\u56de\u6587\u90fd\u53d8\u6210\u5947\u6570\u957f\u5ea6，\u4e2d\u5fc3\u552f\u4e00\u3002<\/p>\n

          \u518d\u52a0\u4e24\u4e2a\u54e8\u5175：<\/p>\n

          \u65b0\u4e32: ^ # a # b # a # $<\/p>\n

            \n
          • \n

            ^ \u548c $ \u662f\u54e8\u5175，\u9632\u6b62\u6269\u5c55\u65f6\u8d8a\u754c<\/p>\n<\/li>\n

          • \n

            \u5b83\u4eec\u4e0d\u76f8\u7b49，\u6269\u5c55\u5230\u8fd9\u91cc\u4e00\u5b9a\u505c\u6b62<\/p>\n<\/li>\n<\/ul>\n

            \u7b2c\u4e8c\u6b65：\u5b9a\u4e49\u534a\u5f84\u6570\u7ec4 p<\/p>\n

            p[i] \u8868\u793a\u4ee5 i \u4e3a\u4e2d\u5fc3\u7684\u56de\u6587\u534a\u5f84（\u5305\u542b\u4e2d\u5fc3）\u3002<\/p>\n

            \u4ee5 "#a#b#a#" \u4e3a\u4f8b：<\/p>\n\ni\u5b57\u7b26p[i]\u56de\u6587<\/tr>\n\n\n\n\n\n\n\n\n
            0<\/td>\n#<\/td>\n0<\/td>\n#<\/td>\n<\/tr>\n
            1<\/td>\na<\/td>\n1<\/td>\n#a#<\/td>\n<\/tr>\n
            2<\/td>\n#<\/td>\n0<\/td>\n#<\/td>\n<\/tr>\n
            3<\/td>\nb<\/td>\n3<\/td>\n#a#b#a#<\/td>\n<\/tr>\n
            4<\/td>\n#<\/td>\n0<\/td>\n#<\/td>\n<\/tr>\n
            5<\/td>\na<\/td>\n1<\/td>\n#a#<\/td>\n<\/tr>\n
            6<\/td>\n#<\/td>\n0<\/td>\n#<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

            \u539f\u4e32\u56de\u6587\u957f\u5ea6 = p[i]（\u56e0\u4e3a\u63d2\u5165 # \u540e，\u534a\u5f84\u6b63\u597d\u7b49\u4e8e\u539f\u4e32\u56de\u6587\u957f\u5ea6）\u3002<\/p>\n

            \u539f\u4e32\u8d77\u59cb\u4f4d\u7f6e = (i – p[i]) \/ 2\u3002<\/p>\n

            \u7b2c\u4e09\u6b65：\u6838\u5fc3\u2014\u2014\u5229\u7528\u5bf9\u79f0\u6027<\/p>\n

            \u5173\u952e\u53d8\u91cf：<\/p>\n

              \n
            • \n

              center：\u5f53\u524d\u6700\u53f3\u56de\u6587\u7684\u4e2d\u5fc3<\/p>\n<\/li>\n

            • \n

              right：\u5f53\u524d\u6700\u53f3\u56de\u6587\u7684\u53f3\u8fb9\u754c（center + p[center]）<\/p>\n<\/li>\n<\/ul>\n

              \u6838\u5fc3\u601d\u60f3：<\/p>\n

              \u5f53\u904d\u5386\u5230 i \u65f6，\u5982\u679c i < right，\u8bf4\u660e i \u5728\u67d0\u4e2a\u56de\u6587\u5185\u90e8\u3002<\/p>\n

              \u5229\u7528\u5bf9\u79f0\u6027，i \u5173\u4e8e center \u7684\u5bf9\u79f0\u70b9\u662f：<\/p>\n

              mirror = 2 * center – i<\/p>\n

              \u6b64\u65f6 p[i] \u81f3\u5c11\u7b49\u4e8e p[mirror]，\u4f46\u6709\u4e24\u79cd\u60c5\u51b5：<\/p>\n

              \u60c5\u51b51: p[mirror] < right – i
              \n \u2192 p[i] = p[mirror]（\u5b8c\u5168\u5bf9\u79f0）<\/p>\n

              \u60c5\u51b52: p[mirror] >= right – i
              \n \u2192 p[i] = right – i（\u53ea\u80fd\u786e\u5b9a\u8fd9\u4e48\u591a，\u9700\u8981\u7ee7\u7eed\u6269\u5c55）<\/p>\n

              \u7edf\u4e00\u5199\u6cd5：<\/p>\n

              if (i < right) {
              \n p[i] = min(right – i, p[mirror]);
              \n}<\/p>\n

              \u56fe\u89e3：<\/p>\n

              center
              \n \u2193
              \n … [ … i … ] …
              \n \u2191 \u2191
              \n mirror right<\/p>\n

              i \u548c mirror \u5173\u4e8e center \u5bf9\u79f0<\/p>\n

              \u7b2c\u56db\u6b65：\u7ee7\u7eed\u6269\u5c55<\/p>\n

              \u786e\u5b9a p[i] \u7684\u4e0b\u754c\u540e，\u7ee7\u7eed\u5411\u4e24\u8fb9\u6269\u5c55：<\/p>\n

              while (t[i + p[i] + 1] == t[i – p[i] – 1]) {
              \n p[i]++;
              \n}<\/p>\n

              \u56e0\u4e3a\u52a0\u4e86\u54e8\u5175 ^ \u548c $，\u4e0d\u4f1a\u8d8a\u754c\u3002<\/p>\n

              \u7b2c\u4e94\u6b65：\u66f4\u65b0 center \u548c right<\/p>\n

              \u5982\u679c i + p[i] > right，\u8bf4\u660e\u627e\u5230\u4e86\u66f4\u9760\u53f3\u7684\u56de\u6587，\u66f4\u65b0：<\/p>\n

              if (i + p[i] > right) {
              \n center = i;
              \n right = i + p[i];
              \n}<\/p>\n

              \u7528\u4f8b\u5b50\u8d70\u4e00\u904d：<\/h4>\n

              s = "babad"<\/p>\n

              \u9884\u5904\u7406：<\/p>\n

              t = "^#b#a#b#a#d#$"
              \n\u4e0b\u6807: 0 1 2 3 4 5 6 7 8 9 10 11 12<\/p>\n

              \u904d\u5386：<\/p>\n\nit[i]mirrorrightp[i]\u8bf4\u660e<\/tr>\n\n\n\n\n\n\n\n\n\n\n\n
              1<\/td>\n#<\/td>\n–<\/td>\n0<\/td>\n0<\/td>\n\u6269\u5c55\u5931\u8d25<\/td>\n<\/tr>\n
              2<\/td>\nb<\/td>\n–<\/td>\n0<\/td>\n1<\/td>\n#b#<\/td>\n<\/tr>\n
              3<\/td>\n#<\/td>\n–<\/td>\n0<\/td>\n0<\/td>\n\u6269\u5c55\u5931\u8d25<\/td>\n<\/tr>\n
              4<\/td>\na<\/td>\n–<\/td>\n0<\/td>\n3<\/td>\n#b#a#b#，center=4, right=7<\/td>\n<\/tr>\n
              5<\/td>\n#<\/td>\n3<\/td>\n7<\/td>\n0<\/td>\ni<right，p[5]=min(2, p[3]=0)=0<\/td>\n<\/tr>\n
              6<\/td>\nb<\/td>\n2<\/td>\n7<\/td>\n1<\/td>\ni<right，p[6]=min(1, p[2]=1)=1<\/td>\n<\/tr>\n
              7<\/td>\n#<\/td>\n1<\/td>\n7<\/td>\n0<\/td>\ni=right，\u6269\u5c55\u5931\u8d25<\/td>\n<\/tr>\n
              8<\/td>\na<\/td>\n–<\/td>\n7<\/td>\n1<\/td>\ni>right，\u6269\u5c55 #a#<\/td>\n<\/tr>\n
              9<\/td>\n#<\/td>\n–<\/td>\n7<\/td>\n0<\/td>\n\u00a0<\/td>\n<\/tr>\n
              10<\/td>\nd<\/td>\n–<\/td>\n7<\/td>\n1<\/td>\n#d#<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

              maxLen = 3, maxCenter = 4<\/p>\n

              start = (4 – 3) \/ 2 = 0
              \n\u7ed3\u679c = s.substr(0, 3) = "bab" \u2705<\/p>\n

              \u4ee3\u7801\u5b9e\u73b0：<\/h4>\n

              class Solution {
              \npublic:
              \n string longestPalindrome(string s) {
              \n \/\/ \u9884\u5904\u7406：\u63d2\u5165 # \u53d8\u6210\u5947\u6570\u957f\u5ea6
              \n string t = "^#";
              \n for (char c : s) {
              \n t += c;
              \n t += '#';
              \n }
              \n t += '$';<\/p>\n

              int n = t.size();
              \n vector<int> p(n, 0);
              \n int center = 0, right = 0;
              \n int maxLen = 0, maxCenter = 0;<\/p>\n

              for (int i = 1; i < n – 1; i++) {
              \n if (i < right) {
              \n p[i] = min(right – i, p[2 * center – i]);
              \n }<\/p>\n

              while (t[i + p[i] + 1] == t[i – p[i] – 1]) {
              \n p[i]++;
              \n }<\/p>\n

              if (i + p[i] > right) {
              \n center = i;
              \n right = i + p[i];
              \n }<\/p>\n

              if (p[i] > maxLen) {
              \n maxLen = p[i];
              \n maxCenter = i;
              \n }
              \n }<\/p>\n

              int start = (maxCenter – maxLen) \/ 2;
              \n return s.substr(start, maxLen);
              \n }
              \n};<\/p>\n

              \u590d\u6742\u5ea6\u5206\u6790：<\/h4>\n\n\u7ef4\u5ea6\u590d\u6742\u5ea6\u8bf4\u660e<\/tr>\n\n\n\n
              \u65f6\u95f4\u590d\u6742\u5ea6<\/td>\nO(n)<\/td>\n\u6bcf\u4e2a\u5b57\u7b26\u6700\u591a\u88ab\u6269\u5c55\u4e00\u6b21<\/td>\n<\/tr>\n
              \u7a7a\u95f4\u590d\u6742\u5ea6<\/td>\nO(n)<\/td>\np \u6570\u7ec4 + \u9884\u5904\u7406\u5b57\u7b26\u4e32<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

              \u4e3a\u4ec0\u4e48\u662f O(n)？
              \n\u56e0\u4e3a right \u53ea\u589e\u4e0d\u51cf，\u6bcf\u6b21\u6269\u5c55\u90fd\u4f1a\u589e\u52a0 right，\u603b\u6269\u5c55\u6b21\u6570\u4e0d\u8d85\u8fc7 n\u3002<\/p>\n

              \u4e09\u79cd\u65b9\u6cd5\u5bf9\u6bd4：<\/h3>\n\n\u65b9\u6cd5\u65f6\u95f4\u590d\u6742\u5ea6\u7a7a\u95f4\u590d\u6742\u5ea6\u4ee3\u7801\u590d\u6742\u5ea6\u63a8\u8350\u5ea6<\/tr>\n\n\n\n\n
              \u4e2d\u5fc3\u6269\u5c55<\/td>\nO(n\u00b2)<\/td>\nO(1)<\/td>\n\u7b80\u5355<\/td>\n\u2b50\u2b50\u2b50\u2b50\u2b50<\/td>\n<\/tr>\n
              \u52a8\u6001\u89c4\u5212<\/td>\nO(n\u00b2)<\/td>\nO(n\u00b2)<\/td>\n\u4e2d\u7b49<\/td>\n\u2b50\u2b50\u2b50\u2b50<\/td>\n<\/tr>\n
              Manacher<\/td>\nO(n)<\/td>\nO(n)<\/td>\n\u590d\u6742<\/td>\n\u2b50\u2b50\u2b50<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

              \u4e2d\u5fc3\u6269\u5c55\u662f\u9762\u8bd5\u9996\u9009：\u4ee3\u7801\u7b80\u6d01，\u7a7a\u95f4 O(1)，\u65f6\u95f4\u590d\u6742\u5ea6 O(n\u00b2) \u5bf9\u5927\u591a\u6570\u573a\u666f\u591f\u7528\u3002<\/p>\n

              \u5173\u952e\u7ec6\u8282：<\/h4>\n

              1. \u4e3a\u4ec0\u4e48\u4e2d\u5fc3\u6269\u5c55\u8981\u5904\u7406\u5947\u5076\u4e24\u79cd\u60c5\u51b5？<\/p>\n

                \n
              • \n

                \u5947\u6570\u56de\u6587："aba"，\u4e2d\u5fc3\u662f\u5355\u4e2a\u5b57\u7b26<\/p>\n<\/li>\n

              • \n

                \u5076\u6570\u56de\u6587："abba"，\u4e2d\u5fc3\u662f\u4e24\u4e2a\u5b57\u7b26\u4e4b\u95f4<\/p>\n<\/li>\n<\/ul>\n

                \u6240\u4ee5\u9700\u8981\u5bf9\u6bcf\u4e2a\u4f4d\u7f6e\u8c03\u7528\u4e24\u6b21\u6269\u5c55：expand(i, i) \u548c expand(i, i+1)\u3002<\/p>\n

                2. \u4e3a\u4ec0\u4e48\u8fd4\u56de right – left – 1？<\/p>\n

                \u5faa\u73af\u7ed3\u675f\u65f6，left \u548c right \u5df2\u7ecf\u8d8a\u754c\u6216\u4e0d\u5339\u914d\u3002\u56de\u6587\u957f\u5ea6 = (right – 1) – (left + 1) + 1 = right – left – 1\u3002<\/p>\n

                3. \u52a8\u6001\u89c4\u5212\u7684\u904d\u5386\u987a\u5e8f<\/p>\n

                \u5fc5\u987b\u6309\u957f\u5ea6\u9012\u589e\u904d\u5386，\u56e0\u4e3a dp[i][j] \u4f9d\u8d56 dp[i+1][j-1]（\u66f4\u77ed\u7684\u5b50\u4e32）\u3002<\/p>\n

                \u603b\u7ed3：<\/h2>\n\n\u8981\u70b9\u8bf4\u660e<\/tr>\n\n\n\n\n\n
                \u6838\u5fc3\u601d\u60f3<\/td>\n\u4ece\u6bcf\u4e2a\u4e2d\u5fc3\u5411\u4e24\u8fb9\u6269\u5c55<\/td>\n<\/tr>\n
                \u5173\u952e\u64cd\u4f5c<\/td>\n\u5947\u6570\u4e2d\u5fc3 (i,i)，\u5076\u6570\u4e2d\u5fc3 (i,i+1)<\/td>\n<\/tr>\n
                \u65f6\u95f4\u590d\u6742\u5ea6<\/td>\nO(n\u00b2)<\/td>\n<\/tr>\n
                \u7a7a\u95f4\u590d\u6742\u5ea6<\/td>\nO(1)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

                \u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"

                \u9898\u76ee\u63cf\u8ff0：\u7ed9\u4f60\u4e00\u4e2a\u5b57\u7b26\u4e32 s，\u627e\u5230 s \u4e2d\u6700\u957f\u7684\u56de\u6587\u5b50\u4e32\u3002\u5982\u679c\u5b57\u7b26\u4e32\u5411\u524d\u548c\u5411\u540e\u8bfb\u90fd\u76f8\u540c，\u5219\u5b83\u6ee1\u8db3 \u56de\u6587\u6027\u3002\u5b50\u5b57\u7b26\u4e32 \u662f\u5b57\u7b26\u4e32\u4e2d\u8fde\u7eed\u7684 \u975e\u7a7a \u5b57\u7b26\u5e8f\u5217\u3002\u793a\u4f8b 1：\u8f93\u5165：s \\”babad\\”
                \n\u8f93\u51fa：\\”bab\\”
                \n\u89e3\u91ca：\\”aba\\” \u540c\u6837\u662f\u7b26\u5408\u9898\u610f\u7684\u7b54\u6848\u3002\u793a\u4f8b 2：\u8f93\u5165：s \\”cbbd\\”
                \n\u8f93\u51fa：\\”bb\\”\u89e3\u9898\u601d\u8def：\u65b9\u6cd5\u4e00&#xff1a<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[55,2692,2865,1813,427],"topic":[],"class_list":["post-114110","post","type-post","status-publish","format-standard","hentry","category-server","tag-c","tag-leetcode","tag-2865","tag-1813","tag-427"],"yoast_head":"\n\u3010\u52a8\u6001\u89c4\u5212-2\u30115.\u6700\u957f\u56de\u6587\u5b50\u4e32 - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.wsisp.com\/helps\/114110.html\" \/>\n<meta property=\"og:locale\" content=\"zh_CN\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"\u3010\u52a8\u6001\u89c4\u5212-2\u30115.\u6700\u957f\u56de\u6587\u5b50\u4e32 - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3\" \/>\n<meta property=\"og:description\" content=\"\u9898\u76ee\u63cf\u8ff0：\u7ed9\u4f60\u4e00\u4e2a\u5b57\u7b26\u4e32 s，\u627e\u5230 s \u4e2d\u6700\u957f\u7684\u56de\u6587\u5b50\u4e32\u3002\u5982\u679c\u5b57\u7b26\u4e32\u5411\u524d\u548c\u5411\u540e\u8bfb\u90fd\u76f8\u540c，\u5219\u5b83\u6ee1\u8db3 \u56de\u6587\u6027\u3002\u5b50\u5b57\u7b26\u4e32 \u662f\u5b57\u7b26\u4e32\u4e2d\u8fde\u7eed\u7684 \u975e\u7a7a \u5b57\u7b26\u5e8f\u5217\u3002\u793a\u4f8b 1：\u8f93\u5165：s "babad" \u8f93\u51fa："bab" \u89e3\u91ca："aba" \u540c\u6837\u662f\u7b26\u5408\u9898\u610f\u7684\u7b54\u6848\u3002\u793a\u4f8b 2：\u8f93\u5165：s "cbbd" \u8f93\u51fa："bb"\u89e3\u9898\u601d\u8def：\u65b9\u6cd5\u4e00&#xff1a\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.wsisp.com\/helps\/114110.html\" \/>\n<meta property=\"og:site_name\" content=\"\u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3\" \/>\n<meta property=\"article:published_time\" content=\"2026-10-08T03:09:04+00:00\" \/>\n<meta name=\"author\" content=\"admin\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"\u4f5c\u8005\" \/>\n\t<meta name=\"twitter:data1\" content=\"admin\" \/>\n\t<meta name=\"twitter:label2\" content=\"\u9884\u8ba1\u9605\u8bfb\u65f6\u95f4\" \/>\n\t<meta name=\"twitter:data2\" content=\"4 \u5206\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.wsisp.com\/helps\/114110.html\",\"url\":\"https:\/\/www.wsisp.com\/helps\/114110.html\",\"name\":\"\u3010\u52a8\u6001\u89c4\u5212-2\u30115.\u6700\u957f\u56de\u6587\u5b50\u4e32 - 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