Why is My C Code Unexpectedly Changing Other Elements in a 2D Array?

[kyacout]

if(gameBoardState[i][col] == 0)
        {
            gameBoardState[i][col] = playerTurn;
            break;
        }

This code is supposed to change the values in gameBoardState[col] (a 2D array), but it changes values in other elements too. For example, when col = 0, and i = 5, gameBoardState[4][6] is changed with the same value as well.

 

[phiby]

if(gameBoardState[i][col] == 0)
        {
            gameBoardState[i][col] = playerTurn;
            break;
        }

This code is supposed to change the values in gameBoardState[col] (a 2D array), but it changes values in other elements too. For example, when col = 0, and i = 5, gameBoardState[4][6] is changed with the same value as well.

How are you sure it's getting changed by this piece of code & not elsewhere?
Did you check this in the debugger?

Also what's the datatype of gameboardState, playerTurn, i & col?