poj2262 Goldbach’s Conjecture

#include<iostream>#include<cstring>#include<cstdio>using namespace std;bool judge(int c){int i;bool flag;if(c%2==0)return 0;for(i=3,flag=1;i*i<=c;i+=2)if(c%i==0){flag=0;break;}if(flag)return 1;return 0;}int main(){int num,i;bool flag;while(1){cin>>num;if(num==0)return 0;for(i=3,flag=1;i<=num/2;i+=2)if(judge(i)&&judge(num-i)){cout<<num<<" = "<<i<<" + "<<num-i<<endl;flag=0;break;}if(flag)cout<<"Goldbach's conjecture is wrong."<<endl;;}return 0;}