I cant figure out why this message is popping up. This is a program that is calculates if it is a leap year.

```
#include <iostream>
using namespace std;
int main()
{
double year, mod4, mod100, mod400;
bool leapYear;
cout << "Enter a year from 1582 on.\n";
cin >> year;
/* 0=False 1=True */
mod4 = year%4;
mod100 = year%100;
mod400 = year%400;
/* If year is divisible by 4 check to see if it is divisible by 100.
If divisible by 100 check to see if it is divisible by 400.
If not it is not a leap year. */
if(mod4=0 && mod100 != 0) leapYear = true;
else if(mod100=0 && mod400=0) leapYear = true;
else leapYear = false;
return 0;
}
```