💻 Caesar Cipher

def caesar_cipher(text, shift, mode="encrypt"):
    if mode == "decrypt":
        shift = -shift
    result = ""
    for char in text:
        if char.isalpha():
            base = ord('A') if char.isupper() else ord('a')
            result += chr((ord(char) - base + shift) % 26 + base)
        else:
            result += char
    return result

print("=== Caesar Cipher ===")
print("Secret messages banao!
")

while True:
    print("1. Encrypt (message chhupao)")
    print("2. Decrypt (message padho)")
    print("3. Brute Force (sabhi shifts try karo)")
    print("4. Baahar jao")
    ch = input("Choice: ")
    if ch == "1":
        msg   = input("Message: ")
        shift = int(input("Shift (1-25): "))
        enc   = caesar_cipher(msg, shift, "encrypt")
        print(f"Encrypted: {enc}")
    elif ch == "2":
        msg   = input("Encrypted message: ")
        shift = int(input("Shift used: "))
        dec   = caesar_cipher(msg, shift, "decrypt")
        print(f"Decrypted: {dec}")
    elif ch == "3":
        msg = input("Encrypted message: ")
        print("
Sabhi possibilities:")
        for s in range(1, 26):
            print(f"  Shift {s:2}: {caesar_cipher(msg, s, 'decrypt')}")
    elif ch == "4":
        break