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来源：互联网发布：安卓版手机编程工具编辑：程序博客网时间：2024/06/03 23:06

#include <iostream>using namespace std;const int MAX = 1000000;const int SIZE = 78500;int P[SIZE];bool isPrime(int num){if (num == 2 || num == 3){return true;}if (num % 6 != 1 && num % 6 != 5){return false;}for (int i = 5; i*i <= num; i += 6){if (num % i == 0 || num % (i+2) == 0){return false;}}return true;}int main(){int sum = -1;int j = 0;for(int i=2;i<MAX;i++)if(isPrime(i))P[j++] = i;while(cin>>sum&&sum!=0){int a = 0;int i = P[a];int j = sum-i;while(i<=j){if(isPrime(j)){cout<<sum<<" = "<<i<<" + "<<j<<endl;break;}i = P[++a];j = sum-i;}if(i>j)cout<<"Goldbach's conjecture is wrong."<<endl;}return 0;}

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#include <iostream>using namespace std;const int MAX = 1000000;const int SIZE = 78500;bool IP[MAX];int P[SIZE];bool isPrime(int num){if (num == 2 || num == 3){return true;}if (num % 6 != 1 && num % 6 != 5){return false;}for (int i = 5; i*i <= num; i += 6){if (num % i == 0 || num % (i+2) == 0){return false;}}return true;}int main(){int sum = -1;int j = 0;for(int i=2;i<MAX;i++){if(isPrime(i)){P[j++] = i;IP[i] = 1;}elseIP[i] = 0;}while(cin>>sum&&sum!=0){int a = 0;int i = P[a];int j = sum-i;while(i<=j){if(IP[j]){cout<<sum<<" = "<<i<<" + "<<j<<endl;break;}i = P[++a];j = sum-i;}if(i>j)cout<<"Goldbach's conjecture is wrong."<<endl;}return 0;}