freeCodeCamp/curriculum/challenges/chinese/08-coding-interview-prep/rosetta-code/evaluate-binomial-coefficients.chinese.md

title	id	challengeType	videoUrl	localeTitle
Evaluate binomial coefficients	598de241872ef8353c58a7a2	5		评估二项式系数

Description

写一个函数来计算给定n和k值的二项式系数。

推荐这个公式：

$ \ binom {n} {k} = \ frac {n！} {（nk）！k！} = \ frac {n（n-1）（n-2）\ ldots（n-k + 1）} { k（k-1）（k-2）\ ldots 1} $

Instructions

Tests

tests:
  - text: <code>binom</code>是一个功能。
    testString: 'assert(typeof binom === "function", "<code>binom</code> is a function.");'
  - text: '<code>binom(5,3)</code>应该返回10。'
    testString: 'assert.equal(binom(5, 3), 10, "<code>binom(5,3)</code> should return 10.");'
  - text: '<code>binom(7,2)</code>应该返回21。'
    testString: 'assert.equal(binom(7, 2), 21, "<code>binom(7,2)</code> should return 21.");'
  - text: '<code>binom(10,4)</code>应该返回210。'
    testString: 'assert.equal(binom(10, 4), 210, "<code>binom(10,4)</code> should return 210.");'
  - text: '<code>binom(6,1)</code>应该返回6。'
    testString: 'assert.equal(binom(6, 1), 6, "<code>binom(6,1)</code> should return 6.");'
  - text: '<code>binom(12,8)</code>应该返回495。'
    testString: 'assert.equal(binom(12, 8), 495, "<code>binom(12,8)</code> should return 495.");'

Challenge Seed

function binom (n, k) {
  // Good luck!
}

Solution

// solution required