C++ Program to Check Whether a Number can be Express as Sum of Two Prime Numbers

C++ Program to Sum of Two Prime Numbers

Source Code:

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#include <iostream> using namespace std; bool checkPrime(int n); int main() { int n, i; bool flag = false; cout << "Enter a positive integer: "; cin >> n; for(i = 2; i <= n/2; ++i) { if (checkPrime(i)) { if (checkPrime(n - i)) { cout << n << " = " << i << " + " << n-i << endl; flag = true; } } } if (!flag) cout << n << " can't be expressed as sum of two prime numbers."; return 0; } // Check prime number bool checkPrime(int n) { int i; bool isPrime = true; for(i = 2; i <= n/2; ++i) { if(n % i == 0) { isPrime = false; break; } } return isPrime; }

Enter a positive integer: 34
34 = 3 + 31
34 = 5 + 29
34 = 11 + 23
34 = 17 + 17