poj 2262

poj 2262

#include<iostream>#include<fstream>#include<algorithm>#include<time.h>using namespace std;/*unsigned __int64 getClock(){__asm{rdtsc;}}*/int main( ){freopen("input.txt","r",stdin);ofstream cout("output.txt");const int NUM=1000010;int *prime=new int[NUM];for(int i=0;i<NUM;i++){prime[i]=1;}for(int i=2;i<NUM;i++){for(int j=2;i*j<NUM;j++){prime[i*j]=0;}}int n;while(scanf("%d",&n)!=EOF){if(prime>1){cout<<n<<" = "<<prime<<" + "<<n-prime<<endl;continue;}int temp=n/2;for(int i=3;i<=temp;i+=2){if(prime[i]==1&&prime[n-i]==1){prime=i;cout<<n<<" = "<<i<<" + "<<n-i<<endl;break;}}}return 0;}