Chapter 1, exercise 3

3.  What does this program do?


#include <stdio.h>


int x, y;


int main(void)
{
  for (x=0; x<10; x++, printf("\n"))
    for (y=0; y<10; y++)
      printf("X");


  return 0;
}

This program prints out ten X's on a line, ten times over.  So it makes a block of 10*10 X's.