Answer L17

#include <stdio.h>
#include <stdlib.h>

/* Puzzle L17 -- print a diagonal line of stars
|
|  Print one star per line. Line 0 has a star in col 0,
|  line one has a star in col 1, and so on for n lines.
*/
int main()
{
  int line, col;
  int n=15 ;
  
  for ( line=0; line < n; line++ )
  {
    for ( col=0; col < line; col++ )
      printf(".");
    printf("*\n");
  }
  
  printf("\n");
  	
  return 0;
}

Comments: It is, perhaps, a "trick", that the star is printed outside of the inner loop. But, how else could you do it?