Every number in an array occure twice except one . Find that number?

#1

#include
using namespace std;

int main()
{

int n;
cin>>n;
int arr[100];
int arr2[100]={0};
for(int i=0;i<n;i++)
{
    cin>>arr[i];
}
for(int i=0;i<n;i++)
{
    arr2[arr[i]]++;
}
for(int i=0;i<n;i++)
{
    if(arr2[arr[i]] < 2)
    cout<<arr[i];
    break;
}
return 0;

}

why is this giving no output ?

#2

You are supposed to do this question using bitmasking concept.
Anyway, please save your code on ide.codingblocks.com and then share its link.

#3

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