HDU1262-寻找素数对

//#include<bits/stdc++.h>
#include<map>
#include<cstdio>
#include<string>
#include<cmath>
#include<iostream>
using namespace std;
int zhishu(int x){
    if(x==2||x==3){
        return 1;
    }
    else{
        int tmp = (int)sqrt(x);
        if(x%2==0){
            return 0;
        }
        for(int i=3;i<=tmp;i+=2){
            if(x % i==0)
                return 0;
        }
        return 1;
    }
}
int main(){
    int M;
    while(scanf("%d",&M)!=EOF){
        for(int i=M/2;i>=3;--i){
            if(zhishu(i)==1 && zhishu(M-i)==1){
                printf("%d %d
",i,M-i);
                break;
            }
        }
    }



    return 0;
}