freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/repeat-a-string-repeat-a-string.english.md

id, title, isRequired, challengeType

id	title	isRequired	challengeType
afcc8d540bea9ea2669306b6	Repeat a String Repeat a String	true	5

Description

Repeat a given string str (first argument) for num times (second argument). Return an empty string if num is not a positive number. Remember to use Read-Search-Ask if you get stuck. Write your own code.

Instructions

Tests

tests:
  - text: '<code>repeatStringNumTimes("*", 3)</code> should return <code>"***"</code>.'
    testString: 'assert(repeatStringNumTimes("*", 3) === "***", "<code>repeatStringNumTimes("*", 3)</code> should return <code>"***"</code>.");'
  - text: '<code>repeatStringNumTimes("abc", 3)</code> should return <code>"abcabcabc"</code>.'
    testString: 'assert(repeatStringNumTimes("abc", 3) === "abcabcabc", "<code>repeatStringNumTimes("abc", 3)</code> should return <code>"abcabcabc"</code>.");'
  - text: '<code>repeatStringNumTimes("abc", 4)</code> should return <code>"abcabcabcabc"</code>.'
    testString: 'assert(repeatStringNumTimes("abc", 4) === "abcabcabcabc", "<code>repeatStringNumTimes("abc", 4)</code> should return <code>"abcabcabcabc"</code>.");'
  - text: '<code>repeatStringNumTimes("abc", 1)</code> should return <code>"abc"</code>.'
    testString: 'assert(repeatStringNumTimes("abc", 1) === "abc", "<code>repeatStringNumTimes("abc", 1)</code> should return <code>"abc"</code>.");'
  - text: '<code>repeatStringNumTimes("*", 8)</code> should return <code>"********"</code>.'
    testString: 'assert(repeatStringNumTimes("*", 8) === "********", "<code>repeatStringNumTimes("*", 8)</code> should return <code>"********"</code>.");'
  - text: '<code>repeatStringNumTimes("abc", -2)</code> should return <code>""</code>.'
    testString: 'assert(repeatStringNumTimes("abc", -2) === "", "<code>repeatStringNumTimes("abc", -2)</code> should return <code>""</code>.");'
  - text: The built-in <code>repeat()</code>-method should not be used
    testString: 'assert(!/\.repeat/g.test(code), "The built-in <code>repeat()</code>-method should not be used");'

Challenge Seed

function repeatStringNumTimes(str, num) {
  // repeat after me
  return str;
}

repeatStringNumTimes("abc", 3);

Solution

function repeatStringNumTimes(str, num) {
  if (num < 0) return ";
  return num === 1 ? str : str + repeatStringNumTimes(str, num-1);
}

repeatStringNumTimes("abc", 3);