poj3461 79ms kmp

#include<cstdio>
#include<cstring>
using namespace std;
//KMP
char str[1000005],sub[10005];
int next[10005];
int len_str,len_sub;
void get_next()
{
    int i = 0,j = -1;
    next[0] = -1;
    while(i<len_sub)
    {
        if(j==-1||sub[i]==sub[j]){
            ++i;
            ++j;
            next[i] = j;
        }
        else j = next[j];
    }
}
void KMP()
{
    get_next();
    int i = 0,j = 0,ans = 0;
    while(i<len_str&&j<len_sub)
    {
        if(j==-1||sub[j]==str[i]) {
            ++i;
            ++j;
        }
        else j = next[j];
        if(j==len_sub)
        {
            ans++;
            j = next[j];
        }
    }
    printf("%d\n",ans);
}
int main()
{
    int n;
    scanf("%d",&n);
    getchar();
    while(n--)
    {
        gets(sub);
        gets(str);
        len_str = strlen(str);
        len_sub = strlen(sub);
        KMP();
    }
    return 0;
}