Pair of Socks problem in cpp, why output is not coming

Question

#include<iostream>
#include<algorithm>
using namespace std;
int sockspair(int a[],int n)
{
sort(a,a+n);
int count=0;
for(int i=0;i<n-1;i+2)
{
if(a[i]==a[i+1])
{
count++;
}
}
return count;
}
int main()
{
int n;
cin>>n;
int a[n];
for(int i=0;i<n;i++)
{
cin>>a[i];
}
int result=sockspair(a,n);
cout<<"Pairs of socks are"<<result;
}

Answer 1

Try to use i += 2 instead of i+2

Answer 2

Thanks bro