How do I fix the "too many arguments to function" error?

Question

I just began to learn how functions work but can't understand very well the issue that I currently have with my code now.

#include <iostream>
using namespace std;

int sumFunction();

int main ()
{
cout << sumFunction(1);

return 0;
}

int sumFunction(int a)
{
int y = a + 1;

return (y);
}

I keep getting an error message saying "too many arguments to function 'int sumFunction () ' ."

Answer 1

The prototype must have the same signature as the implementation.

int sumFunction();
-> int sumFunction(int);