Natalie Cardot 545b8a6f34 Modify if statement (#36088)
* Modify if statement

Change the solution so an empty string is returned when num is less than 1 rather than less than 0 for consistency with instructions.

* Add test 

New test checks that if num is 0, an empty string is returned

* Fix test 

Fixing errors in newly proposed test that checks that empty string is returned when num is 0

* Modify intermediate solution

Changing if statement in intermediate solution to check whether num is less than 1 rather than less than 0. (Also adding curly brackets to that solutions if/else statements.)

* fix: removed unnecessary assert message arguments
2019-05-20 21:08:20 -04:00

2.2 KiB

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) === "***");
  - 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) {
  // repeat after me
  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);