题解

#include<iostream>
using namespace std;
int main(){
    int z; 
    cin >> z;
    for(int i = 4;i <= z;i += 2){
        for(int j = 2;j <= i / 2;j++){
            int x = 0;
            for(int k = 2;k <=j / 2;k++){
                if(j % k == 0){
                    x++;
                    break;
                }
            }
            if(x){
                continue;
            }
            for (int k = 2;k <= (i - j) / 2;k++){
                if((i - j) % k == 0){
                    x++;
                    break;
                }
            }
            if (x){
                continue;
            }
            cout << i << '=' << j << '+' << i - j <<endl;
            break;
        }
    }
    return 0;
}