x.c

#include <stdio.h>
#include "cs50.h"
#include <math.h>

void printX(int dimension)
{
//    dimension -= 2;
    dim = dimension - 2;
    char x[dim][dim];
    int i;
    int j;

    i = 0;
    j = 0;

    for (i = 0; i < dimension; i++){
        for (j = 0; j < dimension; j++){
            if ((i == (dimension-1-j)) ||(i == j)) x[i][j] = '*';
            else x[i][j] = ' ';
        }
    }


    for (i = 0; i < dimension; i++) printf("*");
    printf("\n");
    for (i = 0; i < dimension; i++){
        for (j = 0; j < dimension; j++){
            if (j == 0){
                printf("*");
                printf("%c", x[i][j]);
            } else if (j == dimension - 1){
                printf("%c", x[i][j]);
                printf("*");
            } else {
                printf("%c", x[i][j]);
            }
        }
        printf("\n");
    }
    for (i = 0; i < dimension; i++) printf("*");
}

int main(void)
{
    printX(10);
}