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

id, title, challengeType, forumTopicId

id	title	challengeType	forumTopicId
afcc8d540bea9ea2669306b6	Repeat a String Repeat a String	5	16041

Description

Repeat a given string str (first argument) for num times (second argument). Return an empty string if num is not a positive number.

Instructions

Tests

tests:
  - text: <code>repeatStringNumTimes("*", 3)</code> should return <code>"***"</code>.
    testString: assert(repeatStringNumTimes("*", 3) === "***");
  - text: <code>repeatStringNumTimes("abc", 3)</code> should return <code>"abcabcabc"</code>.
    testString: assert(repeatStringNumTimes("abc", 3) === "abcabcabc");
  - text: <code>repeatStringNumTimes("abc", 4)</code> should return <code>"abcabcabcabc"</code>.
    testString: assert(repeatStringNumTimes("abc", 4) === "abcabcabcabc");
  - text: <code>repeatStringNumTimes("abc", 1)</code> should return <code>"abc"</code>.
    testString: assert(repeatStringNumTimes("abc", 1) === "abc");
  - text: <code>repeatStringNumTimes("*", 8)</code> should return <code>"********"</code>.
    testString: assert(repeatStringNumTimes("*", 8) === "********");
  - text: <code>repeatStringNumTimes("abc", -2)</code> should return <code>""</code>.
    testString: assert(repeatStringNumTimes("abc", -2) === "");
  - text: The built-in <code>repeat()</code> method should not be used.
    testString: assert(!/\.repeat/g.test(code));
  - text:  <code>repeatStringNumTimes("abc", 0)</code> should return <code>""</code>.
    testString: assert(repeatStringNumTimes("abc", 0) === "");
    

Challenge Seed

function repeatStringNumTimes(str, num) {
  return str;
}

repeatStringNumTimes("abc", 3);

Solution

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

repeatStringNumTimes("abc", 3);