UVA 11859 Division Game[Nim游戏]

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <cmath>
using namespace std;
const int N=55;
inline int read(){
    char c=getchar();int x=0,f=1;
    while(c<‘0‘||c>‘9‘){if(c==‘-‘)f=-1;c=getchar();}
    while(c>=‘0‘&&c<=‘9‘){x=x*10+c-‘0‘;c=getchar();}
    return x*f;
}
int n,m,a[N];
int fac(int x){
    int m=sqrt(x)+1,cnt=0;
    for(int i=2;i<=m;i++)
        while(x%i==0) x/=i,cnt++;
    if(x>1) cnt++;
    return cnt;
}
int main(){
    int T=read(),cas=0;
    while(T--){printf("Case #%d: ",++cas);
        n=read();m=read();
        int s=0;
        memset(a,0,sizeof(a));
        for(int i=1;i<=n;i++){ 
            for(int j=1;j<=m;j++) a[i]+=fac(read());
            s^=a[i];
        }
        if(s) puts("YES");
        else puts("NO");
    }
}