hdu1686

#include <iostream>#include <cstdio>#include <cstring>using namespace std;const int maxn = 1000000+9;const int maxn1 = 10000+9;char a[maxn];char b[maxn1];int nextval[maxn1], len1, len2;void get_nextval(){    int i = 0, j = -1;    nextval[0] = -1;    while(i < len2)//它会判断到i = len2 是停止 即 nextval[len2] = x；（某个值）    {        if(j == -1 || b[i] == b[j])        {            if(b[++i] != b[++j]) nextval[i] = j;            else  nextval[i] = nextval[j];        }        else j = nextval[j];    }}int kmp_search(){    get_nextval();    int i = 0,  j = 0, sum = 0;    while(i < len1 && j <= len2)//当j等于len2时 a[i] ！= b[j] = b[len2] 这时 j = nextval[j] 它会继续找 如第二个例子 相当于4个字符 实际只要三个与原串匹配    {        if(j == -1 || a[i] == b[j]) ++i, ++j;        else j = nextval[j];        if(j == len2)        {            ++sum;        }    }    return sum;}int main(){    int t;    cin >> t;    while(t--)    {        cin >> b >> a;        len1 = strlen(a);        len2 = strlen(b);        int w = kmp_search();        printf("%d\n", w);    }}