1.6 KiB
1.6 KiB
title | id | challengeType | videoUrl | localeTitle |
---|---|---|---|---|
Factorial | 597b2b2a2702b44414742771 | 5 | 阶乘 |
Description
编写一个函数来返回一个数字的阶乘。
一个数字的因子由下式给出:
N! = n *(n-1)*(n-2)* ..... * 1例如:3! = 3 * 2 * 1 = 6 4! = 4 * 3 * 2 * 1 = 24
注意:0! = 1
Instructions
Tests
tests:
- text: <code>factorial</code>是一种功能。
testString: 'assert(typeof factorial === "function", "<code>factorial</code> is a function.");'
- text: <code>factorial(2)</code>应该返回一个数字。
testString: 'assert(typeof factorial(2) === "number", "<code>factorial(2)</code> should return a number.");'
- text: <code>factorial(3)</code>应该返回6.“)
testString: 'assert.equal(factorial(3),results[0],"<code>factorial(3)</code> should return 6.");'
- text: <code>factorial(3)</code>应返回120.“)
testString: 'assert.equal(factorial(5),results[1],"<code>factorial(3)</code> should return 120.");'
- text: '<code>factorial(3)</code>应返回3,628,800。“)'
testString: 'assert.equal(factorial(10),results[2],"<code>factorial(3)</code> should return 3,628,800.");'
Challenge Seed
function factorial (n) {
// Good luck!
}
After Test
console.info('after the test');
Solution
// solution required