Thread: Function return value conflict

I'm writing a tic tac toe program and I have a problem with the function that determines whether or not there is a winner. When I try to compile, it gives me an error saying there are conflicting types of the function. All return values should be a character, so I can't figure out what the problem is.

Here is the function:

Code:

char checkWinner (char cell[])
{
        if(cell[0] == cell[1] == cell[2])
        {
                if(cell[0] != ' ')
                {
                return cell[0];
                } else return ' ';
        } else if(cell[3] == cell[4] == cell[5])
        {
                if(cell[3] != ' ')
                {
                return cell[3];
                } else return ' ';
        } else if(cell[6] == cell[7] == cell[8])
        {
                if(cell[6] != ' ')
                {
                return cell[6];
                } else return ' ';
        } else if(cell[0] == cell[3] == cell[6])
        {
                if(cell[0] != ' ')
                {
                return cell[0];
                } else return ' ';
        } else if(cell[1] == cell[4] == cell[7])
        {
                if(cell[1] != ' ')
                {
                return cell[1];
                } else return ' ';
        } else if(cell[2] == cell[5] == cell[8])
        {
                if(cell[2] != ' ')
                {
                return cell[2];
                } else return ' ';
        } else if(cell[0] == cell[4] == cell[8])
        {
                if(cell[0] != ' ')
                {
                return cell[0];
                } else return ' ';
        } else if(cell[2] == cell[4] == cell[6])
        {
                if(cell[2] != ' ')
                {
                return cell[2];
                } else return ' ';
        } else return 'd';


}

Please post the exact error message including line number.

p1.c:121: error: conflicting types for 'checkWinner'


And the error is on line 121, which is actually the line:

char checkWinner(char cell[])

Originally Posted by cashmerelc

p1.c:121: error: conflicting types for 'checkWinner'


And the error is on line 121, which is actually the line:

char checkWinner(char cell[])

You must have a prototype of checkWinner() somewhere that doesn't match this. The exact location of this other definition was probably printed by the compiler.

Code:

if(cell[0] == cell[1] == cell[2])

do you mean this to mean that all these are equal?

Code:

if(cell[0] == cell[1] == cell[2])

do you mean this to mean that all these are equal?

Yeah, do I need to use the && operator between them?

Originally Posted by cashmerelc

Yeah, do I need to use the && operator between them?

Yeah. I missed that one:

Code:

if(cell[0] == cell[1] && cell[1] == cell[2])