#!/usr/bin/env python
"""Implements math functions without using operators except for '+' and '-' """

__author__ = "???"


def add(x, y):
    """Add two integers. Handles negative values."""
    # your code here
    return


def multiply(x, y):
    """Multiply x with y. Handles negative values of x or y."""
    # your code here
    return


def power(x, n):
    """Raise x to power n, where n >= 0"""
    # your code here
    return


def factorial(x):
    """Compute factorial of x, where x > 0"""
    # your code here
    return


def fibonacci(n):
    """Compute the nth term of fibonacci sequence"""
    # your code here
    return


if __name__ == '__main__':
    # your code to call functions above
    pass
