裸的 KMP 算法题．

#include <bits/stdc++.h>
using namespace std;
char s[1000005], p[10005];
int f[10005];
void get_next()
{
    int i = 0, j = -1, len = strlen(p);
    f[0] = -1;
    while (i < len) {
        if (j == -1 || p[i] == p[j]) {
            f[++i] = ++j;
        } else {
            j = f[j];
        }
    }
}
int kmp()
{
    int i = 0, j = 0, len_s = strlen(s), len_p = strlen(p);
    int ans = 0;
    get_next();
    while (i < len_s) {
        if (j == -1 || s[i] == p[j]) {
            i++, j++;
        } else {
            j = f[j];
        }
        if (j == len_p) {
            ans++;
        }
    }
    return ans;
}
int main()
{
    int t;
    scanf("%d", &t);
    while (t--) {
        scanf("%s %s", p, s);
        printf("%d\n", kmp());
    }
    return 0;
}