freeCodeCamp/problem-29-distinct-powers.english.md at 0a330e65f902dcbf750d0f0666c737dd9335f76d

Files

Valeriy 79d9012432 fix(curriculum): quotes in tests (#18828 )

* fix(curriculum): tests quotes

* fix(curriculum): fill seed-teardown

* fix(curriculum): fix tests and remove unneeded seed-teardown

2018-10-20 23:32:47 +05:30

1.9 KiB

Raw Blame History

id, challengeType, title

id	challengeType	title
5900f3891000cf542c50fe9c	5	Problem 29: Distinct powers

Description

Consider all integer combinations of ab for 2 ≤ a ≤ 5 and 2 ≤ b ≤ 5: 22=4, 23=8, 24=16, 25=32 32=9, 33=27, 34=81, 35=243 42=16, 43=64, 44=256, 45=1024 52=25, 53=125, 54=625, 55=3125 If they are then placed in numerical order, with any repeats removed, we get the following sequence of 15 distinct terms: 4, 8, 9, 16, 25, 27, 32, 64, 81, 125, 243, 256, 625, 1024, 3125 How many distinct terms are in the sequence generated by ab for 2 ≤ a ≤ n and 2 ≤ b ≤ n?

Instructions

Tests

tests:
  - text: <code>distinctPowers(15)</code> should return 177.
    testString: assert.strictEqual(distinctPowers(15), 177, '<code>distinctPowers(15)</code> should return 177.');
  - text: <code>distinctPowers(20)</code> should return 324.
    testString: assert.strictEqual(distinctPowers(20), 324, '<code>distinctPowers(20)</code> should return 324.');
  - text: <code>distinctPowers(25)</code> should return 519.
    testString: assert.strictEqual(distinctPowers(25), 519, '<code>distinctPowers(25)</code> should return 519.');
  - text: <code>distinctPowers(30)</code> should return 755.
    testString: assert.strictEqual(distinctPowers(30), 755, '<code>distinctPowers(30)</code> should return 755.');

Challenge Seed

function distinctPowers(n) {
  // Good luck!
  return n;
}

distinctPowers(30);

Solution

const distinctPowers = (n) => {
  let list = [];
  for (let a=2; a<=n; a++) {
    for (let b=2; b<=n; b++) {
      let term = Math.pow(a, b);
      if (list.indexOf(term)===-1) list.push(term);
    }
  }
  return list.length;
};

1.9 KiB Raw Blame History