title: formatting a string :%20s
body: <p>Hi I'm new to java programming 
  while trying to write some simple codes I saw this formatted string 
  I know how it works but my question is about the integer we put between <strong>%</strong> and <strong>s</strong> ...
  at first i thought it might be about the length of the blank field like if it is 5 we will see 5 space characters but i was wrong</p>
  
  <p>if we put any integer smaller than 20 it wont work at all and when i put 20 the field length was 9 space characters...</p>
  
  <p>i would appreciate if you could help me </p>