1.8 KiB
1.8 KiB
id | challengeType | title | videoUrl | localeTitle |
---|---|---|---|---|
5900f3a11000cf542c50feb4 | 5 | Problem 53: Combinatoric selections | 问题53:组合选择 |
Description
nCr = n!r!(n-r)! ,其中r≤n,n! = n×(n-1)×...×3×2×1和0! = 1。
直到n = 23,一个值超过一百万:23C10 = 1144066.对于1≤n≤100,nCr的多少,不一定是不同的值大于一百万?
Instructions
Tests
tests:
- text: <code>combinatoricSelections(1000)</code>应返回4626。
testString: 'assert.strictEqual(combinatoricSelections(1000), 4626, "<code>combinatoricSelections(1000)</code> should return 4626.");'
- text: <code>combinatoricSelections(10000)</code>应该返回4431。
testString: 'assert.strictEqual(combinatoricSelections(10000), 4431, "<code>combinatoricSelections(10000)</code> should return 4431.");'
- text: <code>combinatoricSelections(100000)</code>应返回4255。
testString: 'assert.strictEqual(combinatoricSelections(100000), 4255, "<code>combinatoricSelections(100000)</code> should return 4255.");'
- text: <code>combinatoricSelections(1000000)</code>应该返回4075。
testString: 'assert.strictEqual(combinatoricSelections(1000000), 4075, "<code>combinatoricSelections(1000000)</code> should return 4075.");'
Challenge Seed
function combinatoricSelections(limit) {
// Good luck!
return 1;
}
combinatoricSelections(1000000);
Solution
// solution required