#include<stdio.h>
#include<conio.h>
void extfun();
int num;
void main()
{
extern int num; //External variable declaration
clrscr();
num=10;
printf("%d\n",num);
extfun();
getch();
}
void extfun()
{
extern int num; //External variable declaration
num = num + 50;
printf("%d",num);
}