Given N numbers from 1,2,3 ... N-1 and one other number... Find that one.

Given N numbers from 1,2,3 ... N-1 and one other number... Find that one.

#include<iostream>

using namespace std;
#define N 11
int main()
{
        int array[N] = {1,2,3,4,5,6,7,8,9,10,5};
        int total = 0, sumOfN;

        sumOfN = (N * (N-1)) / 2;

        for(int i=0; i<n; i++)
        {
                total = total + array[i];
        }

        cout << total - sumOfN <<endl;
}