tictactoe/bool-test.c

#include <stdio.h>
#include <stdbool.h>

int main(int argc, char const *argv[])
{
    bool mark[2] = {'X','O'};
    int test = mark;
    printf("mark: %c", test);
    printf("\nnot-mark: %c", !test);

    return 0;
}