1.1 KiB
1.1 KiB
id | title | challengeType | forumTopicId | dashedName |
---|---|---|---|---|
598de241872ef8353c58a7a2 | Evaluate binomial coefficients | 5 | 302259 | evaluate-binomial-coefficients |
--description--
Write a function to calculate the binomial coefficient for the given value of n and k.
This formula is recommended:
\\binom{n}{k} = \\frac{n!}{(n-k)!k!} = \\frac{n(n-1)(n-2)\\ldots(n-k+1)}{k(k-1)(k-2)\\ldots 1}
--hints--
binom
should be a function.
assert(typeof binom === 'function');
binom(5,3)
should return 10.
assert.equal(binom(5, 3), 10);
binom(7,2)
should return 21.
assert.equal(binom(7, 2), 21);
binom(10,4)
should return 210.
assert.equal(binom(10, 4), 210);
binom(6,1)
should return 6.
assert.equal(binom(6, 1), 6);
binom(12,8)
should return 495.
assert.equal(binom(12, 8), 495);
--seed--
--seed-contents--
function binom(n, k) {
}
--solutions--
function binom(n, k) {
let coeff = 1;
for (let i = n - k + 1; i <= n; i++) coeff *= i;
for (let i = 1; i <= k; i++) coeff /= i;
return coeff;
}