Copy String

#include <stdio.h>

void main()

 { 

  char a[20], b[20], i;

  printf("enter the string:- "); 

  gets(a);

  for(i=0; a[i]!='\0'; ++i) 

  b[i]=a[i];

  b[i]='\0';

  printf("String : %s",b); 

  } 

simply it copy one string to another char array..