Pattern in C

pattern1.c

/*
 *      1 2 3 4 5 6 7 8 9  <------ x (i)
 *    1 * * * * * * * * *
 *    2 * * * *   * * * *
 *    3 * * *       * * *
 *    4 * *           * *
 *    5 *               *
 *    ^
 *    |
 *    |
 *    y
 *   (j)
*/
#include<stdio.h>
int main() {
        int x,y;
        printf("Enter a positive odd whole number:  ");
        scanf("%d",&x);
        if (x%2 == 0 || x<0) {
                printf("This program takes only positive odd whole numbers!\n");
        }
        else {
                  y=(x+1)/2;
                  int i,j;
                  for(j=1;j<=y;j++)
                  {
                        for(i=1;i<=x;i++)
                          {
                                if(i<=(y+1-j) || i>=(y+j-1))
                                  {
                                        printf("*");
                                  }
                                else {
                                        printf(" ");
                                  }
                          }
                        printf("\n");
                  }
        }
        return 0;
}