#include <bits/stdc++.h> using namespace std; bool sushu(int n){ bool f = true; int i; for(i = 2;i <= sqrt(n);i++){ if(n % i == 0){ f = false; break; } } if(n <= 1){ f = false; } return f; } int main(){ int a[100][3]; int n,i,j,c = 0,x; cin>>n; for(i = 2;i <= n / 3;i++){ if(sushu(i)){ x = n - i; for(j = i;j <= x / 2;j++){ if(sushu(j) && sushu(x - j)){ a[c][0] = i; a[c][1] = j; a[c][2] = x - j; c++; } } } } cout<<c<<endl; for(i = 0;i < c;i++){ cout<<n<<"="<<a[i][0]<<"+"<<a[i][1]<<"+"<<a[i][2]<<endl; } } /************************************************************** Problem: 1273 User: linmiaoling Language: C++ Result: Accepted Time:11 ms Memory:2072 kb ****************************************************************/