palindrome

身份证和学生卡一起弄丢了,我擦,真蛋疼

这道题是算法导论15章第二题,求最长回文子串

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#include<string.h>
#include<stdlib.h>
#define MAXLEN 50
int (char str[],int n)
{
int dp[n][n];
memset(dp,0,sizeof(dp));
for(int i = 0; i < n;i++)
{
dp[i][i] = 1;
}
for(int len = 2 ; len <= n; len++)
for(int j = 0 ; j < n - len + 1; j++)
{
if(str[j] == str[j + len - 1])
{
dp[j][j + len - 1] = dp[j + 1][j + len - 2] + 2;
}
else
{
dp[j][j + len - 1] = dp[j + 1][j + len - 1] > dp[j][j + len - 2]?dp[j + 1][j + len - 1]:dp[j][j + len - 2];
}
}
return dp[0][n - 1];
}
int main()
{
char str[MAXLEN];
printf("please input your string and press entern");
gets(str);
int res = palindrome(str,strlen(str));
printf("%dn",res);
return 0;
}

这是我的原始代码
思路是dp,dp[i][i] = 1,dp[i]j = dp[i] == dp[j] ? dp[i + 1][j - 1] : max{dp[i][j-1],dp[i-1][j]}