Answer L36

#include <stdio.h>

void center(char ch, int count, int length)
{
  int blanks = length-count;
  int j;
  
  for ( j=0; j<blanks/2; j++ ) putchar( ' ' );
  for ( j=0; j<count;    j++ ) putchar( ch );
  
  putchar( '\n');
}

void triangle(char ch, int rows)
{
  int j;
  
  for ( j=1; j<=rows; j++ )
    center( ch, j*2-1, rows*2-1 );
}

int main()
{
  triangle('*', 12);  
  return 0;
}