#include <stdio.h>

int main() {
   int rows = 0;

   printf("Number of rows: ");
   scanf("%d", &rows);

   for (int i = 1; i <= rows; i++) {
      for (int j = 1; j <= rows-i; j++)
         putchar(' ');
      for (int j = i; j <= 2*i - 1; j++)
         printf("%d", j);
      for (int j = 2*i - 2; j >= i; j--)
         printf("%d", j);
      putchar('\n');
   }
   return 0;  
}