hdu 1711 Number Sequence (KMP - 初步)

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#include <iostream>#include <cstring>#include <string>#include <cstdio>using namespace std;const int N = 1000005;const int M = 10005;int s[N];int t[M];int next[M];void get_next(int len) {    int i, j;    i = 0, j = -1;    next[0] = -1;    while(i < len-1) {        if(j == -1 || t[i] == t[j]) {            i++, j++; next[i] = j;        }        else {            j = next[j];        }    }}int kmp(int sl, int tl) {    int i = 0, j = 0;    while(i < sl && j < tl) {        if(j == -1 || s[i] == t[j]) {            i++, j++;        }        else {            j = next[j];        }    }    if(j == tl) {        return i - j + 1;    }    else return -1;}int main() {    int T, n, m, ans;    cin >> T;    while(T--) {        scanf("%d%d", &n, &m);        int i;        for(i = 0; i < n; i++) {            scanf("%d", s+i);        }        for(i = 0; i < m; i++) {            scanf("%d", t+i);        }        get_next(m);        ans = kmp(n, m);        printf("%d\n", ans);    }    return 0;}