Differentiate between Global & Local variables with examples

Local Variable	Global Variable
Local variables are declared inside a function.	Global Variables are declared before the main function.
Local Variables cannot be accessed outside the function.	Global Variables can be accessed in any function.
Local Variables are alive only for a function.	Global Variables are alive till the end of the program.

Example of local variable.

//program to add any two integers

void main()

{

int a,b,sum;

clrscr();

printf("Enter any two integer value");

scanf("%d%d",&a,&b);

sum=a+b;

printf("\nSum of two integers %d and %d is %d",a,b,sum);

}

Here, a,b, and sum are local variables which are declared in main function.

Example of global variable.

//program to find the sum and difference between two numbers

int a,b,result;

void main()

{

clrscr();

sum();

sub();

getch();

}

sum()

{

printf("Enter two numbers to find their sum");

scanf("%d%d",&a,&b);

result=a+b;

printf("\n the sum of two numbers is %d",result);

return 0;

}

sub()

{

printf("Enter two numbers to find their difference");

scanf("%d%d",&a,&b);

result=a-b;

printf("\n the difference between two numbers is %d",result);

return0;

}

Here, a,b and result are global variables which are declared before the main function.