Kmp 模板 之 hdu 1711 Number Sequence

初学 Kmp ，推荐 严蔚敏教授 的数据结构视频11和12，讲解的很清楚。

#include <iostream>
#include <cstdlib>
#include <cstdio>
using namespace std;
int N, M, next[10005], S[1000005], T[10005];

void getNext() {
    int j = 0, k = -1;
    next[0] = -1;
    while (j < M) {
        if ((-1 == k) || (T[j] == T[k])) {
            ++j; ++k;
            if (T[j] != T[k]) next[j] = k;
            else next[j] = next[k];
        }else k = next[k];
    }
}

int Solve() {
    int i = 0, j = 0;
    while ((i < N) && (j < M)) {
        if ((-1 == j) || (S[i] == T[j])) {
            ++i; ++j;
        }else j = next[j];
    }
    if (M == j) return (i - M + 1);
    else return -1;
}

int main() {
    int Case;
    scanf("%d", &Case);
    while (Case--) {
        scanf("%d %d", &N, &M);
        for (int i = 0; i < N; ++i) {
            scanf("%d", &S[i]);
        }
        for (int j = 0; j < M; ++j) {
            scanf("%d", &T[j]);
        }
        getNext();
        printf("%d
", Solve());
    }
    return 0;
}