that-anta-heli.py

gistfile1.py

#!/usr/bin/python
# Copyright Sudheer Satyanarayana, http://techchorus.net
# All rights reserved.

# That anta heli problem
# a, b, c, d and r are given as input
# Solve the problem
# a x b y c z d = r
# find x, y and z where x, y and z is either +, -, * or /

# The equation should be treated as 
# (( (a x b) y c) z d) = r
# Example problem: 45 x 23 y 34 z 1 = 33
# Solution 45 + 23 - 34 - 1 = 33
# Thus the solution is + - - 

import itertools
import sys

a = 45
b = 23
c = 34
d = 1
r = 33

# answer = + - - 

operators = ['addition', 'subtraction', 'multiplication', 'division']

def operate(x, y, operator):
    if operator == 'addition':
        return x + y
    elif operator == 'subtraction':
        return x - y
    elif operator == 'multiplication':
        return x * y
    elif operator == 'division':
        return x / y

permutations =  itertools.product(operators, repeat=3)

for permutation_tuple in permutations:

    r1 = operate(a, b, permutation_tuple[0])
    r2 = operate(r1, c, permutation_tuple[1])
    r3 = operate(r2, d, permutation_tuple[2])

    if r3 == r:
        print "Found solution"
        print permutation_tuple
        break