poj 1458 dp [最长公共子序列 O(n*m)]

#include <iostream>
#include <cstdio>
#include <cstring>

using namespace std;

int dp[1001][1001];
char s1[1001];
char s2[1001];

int get_max(int a, int b) {
return a > b ? a : b;
}

int main() {
int len1, len2, i, j;
while(scanf("%s%s", s1+1, s2+1) != EOF) {
len1 = strlen(s1+1);
len2 = strlen(s2+1);
for(i = 1; i <= len1; i++) {
dp[i][0] = 0;
}
for(i = 1; i <= len2; i++) {
dp[0][i] = 0;
}
for(i = 1; i <= len1; i++) {
for(j = 1; j <= len2; j++) {
if(s1[i] == s2[j]) dp[i][j] = dp[i-1][j-1] + 1;
else {
dp[i][j] = get_max(dp[i-1][j], dp[i][j-1]);
}
}
}
printf("%d\n", dp[len1][len2]);
}

return 0;
}