💻 GCD LCM Calculator

def gcd(a, b):
    while b:
        a, b = b, a % b
    return a

def lcm(a, b):
    return abs(a * b) // gcd(a, b)

def gcd_steps(a, b):
    steps = []
    while b:
        steps.append(f"  gcd({a}, {b}): {a} % {b} = {a%b}")
        a, b = b, a % b
    steps.append(f"  GCD = {a}")
    return steps, a

print("=== GCD / LCM Calculator ===")
print("GCD = Greatest Common Divisor (sabse bada common factor)")
print("LCM = Least Common Multiple (sabse chhota common multiple)
")

while True:
    print("1. Do numbers ka GCD aur LCM")
    print("2. Step-by-step Euclidean Algorithm")
    print("3. Multiple numbers ka GCD")
    print("4. Fraction simplify karo")
    print("5. Baahar jao")
    ch = input("Choice: ")
    if ch == "1":
        a = int(input("Pehla number: "))
        b = int(input("Doosra number: "))
        print(f"
  GCD({a}, {b}) = {gcd(a, b)}")
        print(f"  LCM({a}, {b}) = {lcm(a, b)}")
        print(f"  Check: {a} x {b} = {a*b} = GCD x LCM = {gcd(a,b)} x {lcm(a,b)} = {gcd(a,b)*lcm(a,b)}")
    elif ch == "2":
        a = int(input("Pehla number: "))
        b = int(input("Doosra number: "))
        steps, result = gcd_steps(a, b)
        print(f"
Euclidean Algorithm:")
        for s in steps:
            print(s)
    elif ch == "3":
        nums = list(map(int, input("Numbers (space se): ").split()))
        result = nums[0]
        for n in nums[1:]:
            result = gcd(result, n)
        print(f"GCD of {nums} = {result}")
    elif ch == "4":
        num = int(input("Numerator (ank): "))
        den = int(input("Denominator (haran): "))
        g   = gcd(num, den)
        print(f"  {num}/{den} = {num//g}/{den//g} (simplified)")
    elif ch == "5":
        break