int_to_roman.py

"""
Given an integer, convert it to a roman numeral.
Input is guaranteed to be within the range from 1 to 3999.
"""

def int_to_roman(num):
    """
    :type num: int
    :rtype: str
    """
    M = ["", "M", "MM", "MMM"];
    C = ["", "C", "CC", "CCC", "CD", "D", "DC", "DCC", "DCCC", "CM"];
    X = ["", "X", "XX", "XXX", "XL", "L", "LX", "LXX", "LXXX", "XC"];
    I = ["", "I", "II", "III", "IV", "V", "VI", "VII", "VIII", "IX"];
    return M[num//1000] + C[(num%1000)//100] + X[(num%100)//10] + I[num%10];

print(int_to_roman(644))