title: Java code length -1 meaning
body: <pre><code>class Zillion {
  
      private int zilly[];
  
      public Zillion(int size){
          zilly = new int[size];
      }
  
      public void increment(){
          int i=zilly.length -1;
          while(i&gt;=0){
              if(zilly[i]!=9){
                  zilly[i]+=1;
                  i=-1;
              }
              else{
                  zilly[i]=0;
                  i--;
              }
          }
      }
  </code></pre>
  
  <p>I just got a basic java code like this and do not know what length -1 means at this part  <code>(int i=zilly.length -1;)</code>.
  Can someone please explain this ?</p>