It is not working. Why???

Question

#include<iostream>
using namespace std;
int main()
{
int n;
cout<<"enter a no.";
cin>> n;
int i=0;
int sum=0;
for(;n*2>i;i+2)
{
sum=sum+i;
}
cout<<sum;
return (0);
}

Answer 1

i+2 should be i+=2

Answer 2

In for loop it should be i+=2

Answer 3

Enter i + = 2 ....bro

Answer 4

Thanks