trouble with c++ while loop ?

Dear All,

I'm having trouble getting my c++ code to work (below). Any suggestions as to what could be the problem? I think it has to do with the while loop, since the program ends before command[0] is a 'Q'.

Thank you in advance.


#include <iostream>

#define MAX 8

using namespace std;

bool validCoord(char col, int row);
void processCoord(string command,char player,string board[MAX][MAX]);
int translateColumn(char letter);
void printboard(string board[MAX][MAX]);


int main(int argc, char *argv[])
{
std::cout << "************************************" << std::endl;
std::cout << "* Welcome to Reversi (Othello) *" << std::endl;
std::cout << "************************************" << std::endl;
std::cout << "" << std::endl;
std::cout << "Player 1 will be X and Player 2 will be O" << std::endl;
std::cout << "Enter ? for a list of commands" << std::endl;

std::cout << "c333333333333333333333333333333333333333333333333 33333333333cc" << std::endl;

std::string command;
std::cin >> command;

std::cout << command << std::endl;

int rows = 8;
int cols = 8;
string board[8][8] = {0};
char player = 'X';

while (command[0] != 'Q') {
if (command[0] == '?') {
std::cout << "? - display list of commands" << std::endl;
std::cout << "<Col><Row> - move to given coordinates" << std::endl;
std::cout << " where <Col> is a column letter (a-h)" << std::endl;
std::cout << " and <Row> is a row number (1-8)" << std::endl;
std::cout << "N - play new game" << std::endl;
std::cout << "P - display board" << std::endl;
std::cout << "Q - quit game" << std::endl;
}

if (command[0] == 'P')
printboard(board);
if (validCoord(command[0],command[1]))
processCoord(command, player, board);

std::cin >> command;


if (player == 'X')
player = 'O';
else
player = 'X';


std::cin >> command;
}
std::cout << "Enter ? for a list of commands" << std::endl;

std::cout << "c333333333333333333333333333333333333333333333333 33333333333cc" << std::endl;

std::string command2;
std::cin >> command2;
std::cout << command2 << std::endl;

return 0;
}

bool validCoord(char col, int row)
{
if (col == 'a' || col == 'b' || col == 'c' || col == 'd' || col == 'e' || col == 'f' || col == 'g' || col == 'h' || col == 'A' || col == 'B' || col == 'C' || col == 'D' || col == 'E' || col == 'F' || col == 'G' || col == 'H') {
if (row == '1' || row == '2' || row == '3' || row == '4' || row == '5' || row == '6' || row == '7' || row == '8')

return true;
else
cout << "Invalid Coordinates (" << col << "," << row << ")." << std::endl;
return false;
}
else
cout << "Invalid Coordinates (" << col << "," << row << ")." << std::endl;
return false;
}

void processCoord(string command,char player, string board[MAX][MAX]) {
if (board[translateColumn(command[0])][command[1]] != "0")
std::cout << "Position (" << command[0] << "," << command[1] << ") is occupied." << std::endl;
else {
if (player == 'X')
board[translateColumn(command[0])][command[1]] = 'X';
else
board[translateColumn(command[0])][command[1]] = 'O';
}
}

int translateColumn(char letter)
{
int col;

if (letter == 'a' || letter == 'A')
col = 1;
if (letter == 'b' || letter == 'B')
col = 2;
if (letter == 'c' || letter == 'C')
col = 3;
if (letter == 'd' || letter == 'D')
col = 4;
if (letter == 'e' || letter == 'E')
col = 5;
if (letter == 'f' || letter == 'F')
col = 6;
if (letter == 'g' || letter == 'G')
col = 7;
if (letter == 'h' || letter == 'H')
col = 8;

return col;
}

void printboard(string board[MAX][MAX])
{
int t;
int w;

cout << " +---+---+---+---+---+---+---+---+" << endl;
for (t = 0;t < MAX; t++)
cout << " " << 8 - t << " " << endl;
for (w = 0;w < MAX; w++)
cout << board[w][8 - t] << " | " << endl;
cout << " +---+---+---+---+---+---+---+---+" << endl;
cout << " a b c d e f g h " << endl;
}

re: trouble with c++ while loop ?

Since you have included this can be simplified to This

can be simplified to Here is your problem

You translate the first character of column from letters to integers but you do not translate the second character, you use it directly. However command[1] does not have the value in the range 0 - 7 which is what is required to be in range for the variable board, it has the range '1' - '8' which is decimal is 49 - 56, well out of range. You need a translateRow function in the same way you have a translate column.

This error appears multiple times in the function processCoord

and finally this also has an error in it, it returns a value between 1 and 8 however this is used as an index into the board array. Since this array is declared string board[8][8] the index needs to be in the range 0 - 7. Additionally this could be written as To use the function tolower you need to include the header ctype.h

re: trouble with c++ while loop ?

Thank you, Banfa, for your help :D