If Else Practice(Calculator with if else Statement)

#include <iostream.h>
#include <conio.h>
int main ()
{
    clrscr();
    float fn,sn;  //declaration for users input.
    float x;  //declaration for answer.
    float c,a=1,s=2,m=3,d=4;  //declaration "c" for user input and others are for +,-,*,/.
    cout <<"WELLCOM TO CALCULATOR IN C++" <<endl;
    cout <<"Enter First Number : ";
    cin >> fn;  //first number
    cout <<"\n Enter Opration Sign That You Want To Perform According To Menu" <<endl;
    cout <<"   MENU \n 1 Is For Addition \n 2 Is For Subtraction \n 3 Is For Multiplacation \n 4 Is For Division " <<endl;  //menu
    cout <<" OPRATION SIGN = ";
    cin >> c;
    cout <<"\nEnter Your Scond Number : ";
    cin >> sn;  //scond number
    cout <<endl;
    if (c==a)
    {
        x=fn+sn;
        cout <<" The Sum Is = "<< x <<endl;
    }
    else if (c==s)
    {
        x=fn-sn;
        cout <<"The Difference Is = "<< x <<endl;
    }
    else if (c==m)
    {
        x=fn*sn;
        cout <<" The Multiplacation Is = "<< x <<endl;
    }
    else if (c==d)
    {
        x=fn/sn;
        cout <<"The Division Is = "<< x <<endl;
    }
    getch();
    return 0;
}