freecodecamp--freecodecamp/curriculum/challenges/english/blocks/daily-coding-challenges-python/6a1d9f98e819ed70a0e994e0.md

id, title, challengeType, dashedName

id	title	challengeType	dashedName
6a1d9f98e819ed70a0e994e0	Challenge 334: Exact Change	29	challenge-334

--description--

Given an integer amount in cents, return the number of distinct ways to make exact change using pennies (1 cent), nickels (5 cents), dimes (10 cents), and quarters (25 cents).

--hints--

exact_change(3) should return 1.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(exact_change(3), 1)`)
}})

exact_change(9) should return 2.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(exact_change(9), 2)`)
}})

exact_change(17) should return 6.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(exact_change(17), 6)`)
}})

exact_change(39) should return 24.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(exact_change(39), 24)`)
}})

exact_change(61) should return 73.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(exact_change(61), 73)`)
}})

exact_change(99) should return 213.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(exact_change(99), 213)`)
}})

--seed--

--seed-contents--

def exact_change(amount):

    return amount

--solutions--

def exact_change(amount):
    coins = [1, 5, 10, 25]
    dp = [0] * (amount + 1)
    dp[0] = 1
    for coin in coins:
        for i in range(coin, amount + 1):
            dp[i] += dp[i - coin]
    return dp[amount]