Goldbach conjecture (split into prime numbers and

# The meaning of problems

Goldbach conjecture 4 is greater than any one of said even number can be removed and the two odd primes, there are multiple groups, a given n,

Ask whether there is a group of odd prime satisfying the above, when more than one set of differencing largest group

n ∈ [6,1e6]

# Explanations

Pretreatment all prime numbers, all in addition to the two primes are all odd, it can Laid-off determination, determining a prime number, it is determined by np is prime to

From small to large prime number enumeration to ensure that the maximum difference

 1 #include<bits/stdc++.h>
 2 using namespace std;
 3 const int N=1e6+10;
 4 int p[N],cnt;
 5 bool st[N];
 6 int n;
 7 void get_primes(int n){
 8     for(int i=2;i<=n;i++){
 9         if(!st[i]) p[cnt++]=i;
10         for(int j=0;p[j]<=n/i;j++){
11             st[p[j]*i]=true;
12             if(i%p[j]==0) break;
13         }
14     }
15 }
16 int main(){
17     get_primes(N);
18     while(cin>>n,n){
19         for(int i=1;i<cnt;i++){
20             int a=p[i];
21             int b=n-a;
22             if(!st[b]){
23                 printf("%d = %d + %d\n",n,a,b);
24                 break;
25             }
26 
27         }
28     }
29 }