KMP算法

#include<stdio.h>
#include<string.h>
const int N = 10010;
char T[1000010], P[N];
int pi[N];
int ans;
void COMPUTER_PREFIX_FUNCTION(){
        int m = strlen(P), i, k;
        for(k = pi[0] = -1, i = 1; i < m; i++){
            while(k > -1 && P[k+1] != P[i])
                k = pi[k];
            if(P[k+1] == P[i])
                k++;
            pi[i] = k;
        }
}
void KMP_MATCHER(){
        int i, n, m, k;
        n = strlen(T); m = strlen(P);
        for(k = -1, i = 0; i < n; i++){
            while(k > -1 && P[k+1] != T[i])    k = pi[k];
            if(P[k+1] == T[i])    k++;
            if(k == m-1){
                ans ++;
                k = pi[k];
            }
        }
}
 int main(){
    //freopen("data.in", "r", stdin);
    int n;
    scanf("%d", &n);
    while(n--) {
        scanf("%s %s", P, T);
        ans = 0;
        COMPUTER_PREFIX_FUNCTION();
        KMP_MATCHER();
        printf("%d\n", ans);
    }
    return 0;
 }