def to_lower(text):
    result = ""
    for char in text:
        code = ord(char)
        if 65 <= code and code <= 90:
            result = result + chr(code + 32)
        else:
            result = result + char
    return result

print(to_lower("Hello World"))

def caesar_encrypt(text, shift):
    result = ""
    for char in text:
        code = ord(char)
        if 65 <= code and code <= 90:
            new_code = (code - 65 + shift) % 26 + 65
            result = result + chr(new_code)
        elif 97 <= code and code <= 122:
            new_code = (code - 97 + shift) % 26 + 97
            result = result + chr(new_code)
        else:
            result = result + char
    return result

print(caesar_encrypt("Hello", 3))
print(caesar_encrypt("Khoor", -3))
