A program to find subtraction of two number

#include<stdio.h>;
#include<conio.h>;
void main()
{
    int a,b,sub;
    printf("enter first number");
    scanf("%d",&a);
    printf("enter second number");
    scanf("%d",&b);
    sub=a-b;
    printf("the subtraction is %d",sub);
    getch();
}

or

#include<stdio.h>;
#include<conio.h>;
void main()
{
    int a,b,sub;
    printf("enter both number  number n ");
    scanf("%d%d",&a,&amp;b);

    sum=a-b;
    printf("the subtraction  is %d",sub);
    getch();
}

or

#include<stdio.h>;
#include<conio.h>;
void main()
{
    int a,b;
    printf("enter both number  number n ");
    scanf("%d%d",&a,&amp;b);
    printf("the subtraction is %d",a-b);
    getch();
}