freecodecamp--freecodecamp/curriculum/challenges/english/blocks/daily-coding-challenges-python/6a2037a68a0bc2aef0006004.md

id, title, challengeType, dashedName

id	title	challengeType	dashedName
6a2037a68a0bc2aef0006004	Challenge 342: Dice Odds	29	challenge-342

--description--

Given a number of six-sided dice to roll and a target sum, return the odds of rolling that sum as a string in the format "1 in X".

• The number of dice will be between 1 and 6.
• The target sum is always achievable with the given number of dice.
• Round "X" to the nearest whole number.

--hints--

get_odds(1, 5) should return "1 in 6".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(get_odds(1, 5), "1 in 6")`)
}})

get_odds(2, 4) should return "1 in 12".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(get_odds(2, 4), "1 in 12")`)
}})

get_odds(3, 10) should return "1 in 8".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(get_odds(3, 10), "1 in 8")`)
}})

get_odds(4, 7) should return "1 in 65".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(get_odds(4, 7), "1 in 65")`)
}})

get_odds(5, 26) should return "1 in 111".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(get_odds(5, 26), "1 in 111")`)
}})

get_odds(6, 35) should return "1 in 7776".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(get_odds(6, 35), "1 in 7776")`)
}})

--seed--

--seed-contents--

def get_odds(dice, target):

    return dice

--solutions--

def get_odds(dice, target):
    valid_combos = 0
    total_combos = 6 ** dice

    def roll(dice_left, total):
        nonlocal valid_combos
        if dice_left == 0:
            if total == target:
                valid_combos += 1
            return
        for face in range(1, 7):
            roll(dice_left - 1, total + face)

    roll(dice, 0)
    return f"1 in {round(total_combos / valid_combos)}"