hdu 1711 水kmp

/**********************jibancanyang************************** *Author        :jibancanyang *Created Time  : Thu 28 Apr 2016 01:21:08 PM CST *File Name     : hdu1711.cpp *Problem: 水kmp *Get:***********************[e-mail]**********************/#include <cstdio>#include <cstring>#include <iostream>#include <algorithm>#include <vector>#include <queue>#include <set>#include <map>#include <string>#include <cmath>#include <cstdlib>#include <ctime>#include <stack>using namespace std;typedef pair<int, int> pii;typedef long long ll;typedef unsigned long long ull;vector<int> vi;#define pr(x) cout << #x << ": " << x << "  "#define pl(x) cout << #x << ": " << x << endl;#define xx first#define yy second#define sa(n) scanf("%d", &(n))#define rep(i, a, n) for (int i = a; i < n; i++)#define vep(c) for(decltype((c).begin() ) it = (c).begin(); it != (c).end(); it++)const int mod = int(1e9) + 7, INF = 0x3fffffff, maxn = 1e6 + 12;int s[maxn], p[maxn ];int plen, slen, nexts[maxn];void getnexts(void){    nexts[0] = -1;    int k = -1, j = 0;    while (j < plen - 1) {        if (k == -1 || p[k] == p[j]) {            k++; j++;            if (p[k] != p[j]) nexts[j] = k;            else nexts[j] = nexts[k];        } else k = nexts[k];    }}int kmp(void){    int i = 0, j = 0;    while (i < slen && j < plen) {        if (j == -1 || s[i] == p[j]) i++, j++;        else j = nexts[j];    }    if (j == plen) return i - j + 1;    else return -1;}int main(void){#ifdef LOCAL    //freopen("in.txt", "r", stdin);    //freopen("out.txt", "w", stdout);#endif    cin.sync_with_stdio(false);    int T;    sa(T);    while (T--) {        sa(slen), sa(plen);        for (int i = 0; i < slen; i++) sa(s[i]);        rep (i, 0, plen) sa(p[i]);        getnexts();        printf("%d\n", kmp());    }    return 0;}