HDU 1686 Oulipo

http://acm.hdu.edu.cn/showproblem.php?pid=1686

求子串个数，可重复，直接上KMP模板

View Code

#include <iostream>

#include <queue>

using namespace std ; 

int n,m;

char a[1000002],b[10002];

int _next[1000002];

int ans;

void Init_()

{

    int i,k;  

    i = 0; k = -1; _next[0] = -1;  

    while(i < m){  

        if(k == -1 || b[i] == b[k]){  

            i++;k++;  

            if(b[i] != b[k])  

                _next[i] = k;  

            else  

                _next[i] = _next[k];  

        }  

        else  

            k = _next[k];  

    }  

}

void kmp()

{

    int i,j;  

    i = 0;j = 0;  

    while(i < n && j < m){  

        if(j == -1 || a[i] ==  b[j]){  

            i++;j++;  

        }  

        else  

            j = _next[j];

        if(j == m)

           {

               ans++;

            j=_next[j];

        }

    }    

}

int main()

{

    int t;

    scanf("%d",&t);

    while(t--)

    {

        scanf("%s%s",b,a);

        n=strlen(a);

        m=strlen(b);

        Init_();

        ans=0;

        kmp();

        printf("%d\n",ans);

    }

    return 0;

}