Thread: Difference between the outputs.

I am new to C programming. Please , tell me , why there is difference between the outputs of the two programs below.

Code:

 #include<stdio.h>
int main()
{
  int i=0,j=0;




  for(;i<=20;i++)
     {
         for(;j<=10;j++)
            {
                     printf("%d\t%d\n",i,j);
            }


     }
     return 0;
  }

Code:

 #include<stdio.h>
int main()
{
  int i,j;




  for(i=1;i<=20;i++)
     {
         for(j=1;j<=10;j++)
            {
                     printf("%d\t%d\n",i,j);
            }


     }
     return 0;
  }