freeCodeCamp

1.9 KiB

Raw Blame History

id	challengeType	title	videoUrl	localeTitle
5900f3a11000cf542c50feb4	5	Problem 53: Combinatoric selections

Description

Existem exatamente dez maneiras de selecionar três de cinco, 12345: 123, 124, 125, 134, 135, 145, 234, 235, 245 e 345. Em combinatória, usamos a notação, 5C3 = 10. Em geral,

nCr = n! r! (n − r)! , onde r ≤ n, n! = n × (n − 1) × ... × 3 × 2 × 1 e 0! = 1

Não é até n = 23, que um valor excede um milhão: 23C10 = 1144066. Quantos, não necessariamente distintos, valores de nCr, para 1 ≤ n ≤ 100, são maiores que um milhão?

Instructions

Tests

tests:
  - text: <code>combinatoricSelections(1000)</code> deve retornar 4626.
    testString: 'assert.strictEqual(combinatoricSelections(1000), 4626, "<code>combinatoricSelections(1000)</code> should return 4626.");'
  - text: <code>combinatoricSelections(10000)</code> deve retornar 4431.
    testString: 'assert.strictEqual(combinatoricSelections(10000), 4431, "<code>combinatoricSelections(10000)</code> should return 4431.");'
  - text: <code>combinatoricSelections(100000)</code> deve retornar 4255.
    testString: 'assert.strictEqual(combinatoricSelections(100000), 4255, "<code>combinatoricSelections(100000)</code> should return 4255.");'
  - text: <code>combinatoricSelections(1000000)</code> deve retornar 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

1.9 KiB Raw Blame History Unescape Escape