HDU_1711 Number Sequence(KMP)

第一道kmp的题目，没想到纠结在上边这么多时间，也不知道哪错了，反正改着改着就对了。。。

#include <iostream>
#include <cstdio>
using namespace std;
const int maxn = 1000000;
const int maxm = 10000;

int a[maxn+10], b[maxm+10];
int next[maxm+10];

void get_next(int num[], int m)
{
    next[0] = -1;
    for(int i = 1, j = -1; i < m; i++)
    {
        while(j >= 0 && num[j+1] != num[i])
            j = next[j];
        if(num[j+1] == num[i])
            j++;
        next[i] = j;
    }
}

int kmp(int a[], int b[], int n, int m)
{
    get_next(b, m);
    for(int i = 0, j = -1; i < n; i++)
    {
        while(j >= 0 && b[j+1] != a[i])
            j = next[j];
        if(b[j+1] == a[i])
            j++;
        if(j == m-1)
            return i-j+1;
    }
    return -1;
}

int main()
{
    //freopen("data.in", "r", stdin);
    int t, n, m;
    while(scanf("%d", &t)!= EOF)
    {
        while(t--)
        {
            scanf("%d%d", &n, &m);
            for(int i = 0; i < n; i++)
                scanf("%d", a+i);
            for(int j = 0; j < m; j++)
                scanf("%d", b+j);
            printf("%d\n", kmp(a, b, n, m));
        }
    }
    return 0;
}