Comparing and replacing character arrays

[smeyer27]

Hi, I'm trying to write a function that would allow me to take a user's input and compare it against the letters from a file that is being scanned in. And if the letter matches one from the file, it would replace a character in a different array at a specific element. So far this is what I have:

int CompareGuess(char actualPtr[], char letterGuess, int num)
{
	int i;

	for (i=0; i<num; i++)
	{
		if (actualPtr[i] = letterGuess)
		{
			return i;
		}
		return -1;
	}
}

I'm stuck after this point. Any help would be greatly appreciated