Matrix Matcher

Matrix Matcher

代码

#include <bits/stdc++.h>
using namespace std;
const int M=1005;
using ull=unsigned long long;
const ull P1=131,P2=233;

string s1[M],s2[M];
ull num[M][M],base1[M],base2[M];
void init() {
    base1[0]=base2[0]=1;
    for(int i=1;i<M;i++) {
        base1[i]=base1[i-1]*P1;
        base2[i]=base2[i-1]*P2;
    }
}

void build(int n,int m,string s[]) {
    for(int i=1;i<=n;i++)for(int j=1;j<=m;j++)
        num[i][j]=num[i-1][j]*P1+num[i][j-1]*P2-num[i-1][j-1]*P1*P2+s[i][j];
}

ull get(int x1,int y1,int x2,int y2) {
    return num[x2][y2]-num[x1-1][y2]*base1[x2-x1+1]-num[x2][y1-1]*base2[y2-y1+1]
        +num[x1-1][y1-1]*base1[x2-x1+1]*base2[y2-y1+1];
}

int main() {
    init();
    int TT;cin>>TT;
    while(TT--) {
        int ans=0;
        int n,m;cin>>n>>m;
        for(int i=1;i<=n;i++) {
            cin>>s1[i];
            s1[i]='?'+s1[i];
        }
        int  x,y;cin>>x>>y;
        for(int i=1;i<=x;i++) {
            cin>>s2[i];
            s2[i]='?'+s2[i];
        }
        build(x,y,s2);
        int tmp=num[x][y];
        build(n,m,s1);
        for(int i=1;i+x-1<=n;i++)for(int j=1;j+y-1<=m;j++)
            if(tmp==get(i,j,i+x-1,j+y-1))ans++;
        cout<<ans<<'\n';
    }
    return 0;
}