two number sum in cpp code example

Example 1: two sum problem in c++

bool twosum(int A[], int N, int X) {
  	sort(A, A+N);
    int i = 0, j = N-1;
    while (i < j) {
        if (A[i] + A[j] == X) return true;
        else if (A[i] + A[j] > X) j--;
        else i++;
    }
    return false;
}

Example 2: sum of two numbers c++

#include<iostream>
using namespace std;
int main()
{
	double number1,number2;
  	double sum0;
  	sum=number1+number2;
  	cout<<sum;
}