ZOJ 3957 Knuth-Morris-Pratt Algorithm

#include<bits/stdc++.h>
using namespace std;

char s[2000];

int main()
{
    int T; scanf("%d",&T);
    while(T--)
    {
        scanf("%s",s);
        int ans=0;
        int len=strlen(s);
        for(int i=0;i<len-2;i++)
        {
            if(s[i]==‘d‘&&s[i+1]==‘o‘&&s[i+2]==‘g‘) ans++;
            if(s[i]==‘c‘&&s[i+1]==‘a‘&&s[i+2]==‘t‘) ans++;
        }
        printf("%d\n",ans);
    }
    return 0;
}