最长回文子串 c语言

以下是C语言实现最长回文子串的例子：

#include <stdio.h>
#include <string.h>

char* longestPalindrome(char* s) {
    int len = strlen(s);
    if (len < 2) {
        return s;
    }
    int maxLen = 1;
    int begin = 0;
    int dp[len][len];
    memset(dp, 0, sizeof(dp));
    for (int i = 0; i < len; i++) {
        dp[i][i] =1;
    }
    for (int L = 2; L <= len; L++) {
        for (int i = 0; i < len; i++) {
            int j = i + L - 1;
            if (j >= len) {
                break;
            }
            if (s[i] != s[j]) {
                dp[i][j] = 0;
            } else {
                if (j - i < 3) {
                    dp[i][j] = 1;
                } else {
                    dp[i][j] = dp[i + 1][j - 1];
                }
            }
            if (dp[i][j] && j - i + 1 > maxLen) {
                maxLen = j - i + 1;
                begin = i;
            }
        }
    }
    s[maxLen + begin] = '\0';
    return s + begin;
}

int main() {
    char s[] = "babad";
    printf("%s\n", longestPalindrome(s)); // 输出：bab
    return 0;
}