FUNCTIONS
=========
RETURNING MULTIPLE VALUES FROM FUNCTION
========================================
# Returning Multiple Values from function

def ariths():
    d1 = int(input("Enter a value:"))
    d2 = int(input("Enter a value:"))

    s_add = d1 + d2
    s_sub = d1 - d2
    s_prod = d1 * d2

    return s_add,s_sub,s_prod

res1,res2,res3 = ariths()

print("The Addition is = ",res1)
print("The Subtraction is = ",res2)
print("The Product is = ",res3)

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Ways to Represent the arguments in function
===========================================
4-ways to represent arguments/parameters in function:
1) positional Arguments
========================

# Positional Arguments

def function(a,b,c,d):  # a,b,c and d ==> Formal Arguments
    if a == b == c == d:
        print("It is a Square.")
        area_square = a ** 2
        return area_square
    elif a == c and b == d:
        print("It is a Rectangle.")
        area_rectangle = a * c
        return area_rectangle
    else:
        print("Not possible to calculate any")
        return "None"

p = 9
q = 7
r = 9
s = 7

area = function(11,11,11,11)
area1 = function(p,r,s,q)   # p,q,r and s ==> Actual Arguments

print("The Area is = ",area)
print("The Area is = ",area1)

==============================================

2) Keyword Arguments
====================

# Keyword Arguments

def printGreetings(name):
    print("Hi,",name,"Good Morning")

printGreetings("Ravi")
n = input("Enter the name of the candidate:")
printGreetings(name = n)    # argument is name, for the argument we have assigned value from 'n'

==============================

def rect(length,breadth):
    circum = 2 *(length + breadth)
    return circum

l = int(input("Enter a length value:"))
b = int(input("Enter a breadth value:"))

result = rect(length = l,breadth = b)
res1 = rect(length = l, breadth = l)

print(result)
print(res1)

3) Default Arguments
=====================
# Default Arguments

def printGreetings(name = "user"):
    print("Hi",name,",Have a great day.")

printGreetings()    # without any value to the parameter
printGreetings("Rakesh")

4) Variable Length Arguments
============================

# Variable Length Arguments

def Summing(*args):
    total = 0
    for i in args:
        total += i

    print("The Total = ",total)

Summing()   # function call with 0 arguments
Summing(10) # function call with 1 argument
Summing(100,200,300,400,500)
Summing(1,2,3,4,5,6,7,8,9,10)

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Scope of Variables:
===================
Two types of scopes:
1) Local Scope ==> Local Variables/function variables
=======================================================
==> are always allowed to define inside the function.
scope ==> within the same function.

# Types of Variables

def fun():
    a = 10
    b = 20  # local Variables
    print(a,b)

=========================

fun()
# print(a);print(b)

def fun():
    a = 100
    b = 200

    for i in range(5):
        c = 10
        res = i + c
        print(res)
    print(c)

fun()

2) Global Scope ==> Global Variables
======================================
the variables from outside the function ==> Global variables
we can access in anywhere of the program

# Global Variables

a = 10
b = 20

def fun1():
    global a,b
    a = 100
    b = 200
    print(a)
    print(b)

def fun2():
    print(a)
    print(b)

print(a)
print(b)
fun1()
fun2()
print(a)
print(b)

=======================================

Recursion:
==========
A function that calls itself again and again is known as "recursion".
that function ===> Recursive function.

# Recursion

# Program to find the factorial of a number using recursion
"""
5! = 5 * 4 * 3 * 2 * 1
5! = 5 X fact(4)
 ==> 5 X 4 X fact(3)
 ==> 20 X 3 X fact(2)
 ==> 60 X 2 X fact(1)
 ==> 120 X 1 X fact(0)
 ==> 120 X 1 ==> 120
"""

def factorial(num):
    if num == 0:
        fact = 1
    else:
        fact = num * factorial(num-1)
    return fact

print("The Factorial of 5 is = ",factorial(5))
print(factorial(7))