Predict the Outputs Of the following codes :

1) 

#include<stdio.h>
void main()
{
  int i;
  for(;scanf("%d",&i);printf("%d",i))
  ;
}

O/p: the for loop will be executed infinite number of times.\

eg:    

     8

     8

     10

     10

2)

#include<stdio.h>
void main()
{
    extern int i;
    i=20;
    printf("%d",sizeof(i));
}


// O/p: error.  because extern int i is a declaration and not a definition.

3)

#include<stdio.h>
void main()
{
     extern int a;
     printf("%d",a);
}


int a=20;

//Output :: 20

4)

#include<stdio.h>
void main()
{
    char *s1;
    char far *s2;
    char near *s3;
    char huge *s4;
    printf("%d %d %d %d", sizeof(s1),sizeof(s2),sizeof(s3),sizeof(s4));
}

// Output :  4 4 2 4