Algorithm puzzle

[yhrght12]

I am currently taking a cs class and have this assignment. I am completely lost, so any help would be greatly appreciated. Heres the question. Thank you.

In cryptarithmetic puzzles, mathematical equations are written using letters. Each letter
can be a digit from 0 to 9, but no two letters can be the same. Here is a sample problem:
SEND + MORE = MONEY
A solution to the puzzle is S = 9, R = 8, O = 0, M = 1, Y = 2, E = 5, N = 6, D = 7
Write a program that finds solutions to the following cryptarithmetic puzzle:
TOO + TOO + TOO + TOO = GOOD
The simplest technique is to use a nested loop for each unique letter (in this case T, O, G,
D). The loops would systematically assign the digits from 0– 9 to each letter. For
example, it might first try T = 0, O = 0, G = 0, D = 0, then T = 0, O = 0, G = 0, D = 1,
then T = 0, O = 0, G = 0, D = 2, etc. up to T = 9, O = 9, G = 9, D = 9. In the loop body,
test that each variable is unique and the equation is satisfied. Output the values for the
letters that satisfy the equation.