freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../basic-algorithm-scripting/confirm-the-ending.english.md

4.3 KiB

id title isRequired challengeType
acda2fb1324d9b0fa741e6b5 Confirm the Ending true 5

Description

Check if a string (first argument, str) ends with the given target string (second argument, target). This challenge can be solved with the .endsWith() method, which was introduced in ES2015. But for the purpose of this challenge, we would like you to use one of the JavaScript substring methods instead. Remember to use Read-Search-Ask if you get stuck. Write your own code.

Instructions

Tests

tests:
  - text: '<code>confirmEnding("Bastian", "n")</code> should return true.'
    testString: 'assert(confirmEnding("Bastian", "n") === true, ''<code>confirmEnding("Bastian", "n")</code> should return true.'');'
  - text: '<code>confirmEnding("Congratulation", "on")</code> should return true.'
    testString: 'assert(confirmEnding("Congratulation", "on") === true, ''<code>confirmEnding("Congratulation", "on")</code> should return true.'');'
  - text: '<code>confirmEnding("Connor", "n")</code> should return false.'
    testString: 'assert(confirmEnding("Connor", "n") === false, ''<code>confirmEnding("Connor", "n")</code> should return false.'');'
  - text: '<code>confirmEnding("Walking on water and developing software from a specification are easy if both are frozen"&#44; "specification"&#41;</code> should return false.'
    testString: 'assert(confirmEnding("Walking on water and developing software from a specification are easy if both are frozen", "specification") === false, ''<code>confirmEnding("Walking on water and developing software from a specification are easy if both are frozen"&#44; "specification"&#41;</code> should return false.'');'
  - text: '<code>confirmEnding("He has to give me a new name", "name")</code> should return true.'
    testString: 'assert(confirmEnding("He has to give me a new name", "name") === true, ''<code>confirmEnding("He has to give me a new name", "name")</code> should return true.'');'
  - text: '<code>confirmEnding("Open sesame", "same")</code> should return true.'
    testString: 'assert(confirmEnding("Open sesame", "same") === true, ''<code>confirmEnding("Open sesame", "same")</code> should return true.'');'
  - text: '<code>confirmEnding("Open sesame", "pen")</code> should return false.'
    testString: 'assert(confirmEnding("Open sesame", "pen") === false, ''<code>confirmEnding("Open sesame", "pen")</code> should return false.'');'
  - text: '<code>confirmEnding("Open sesame", "game")</code> should return false.'
    testString: 'assert(confirmEnding("Open sesame", "game") === false, ''<code>confirmEnding("Open sesame", "game")</code> should return false.'');'
  - text: '<code>confirmEnding("If you want to save our world, you must hurry. We dont know how much longer we can withstand the nothing", "mountain")</code> should return false.'
    testString: 'assert(confirmEnding("If you want to save our world, you must hurry. We dont know how much longer we can withstand the nothing", "mountain") === false, ''<code>confirmEnding("If you want to save our world, you must hurry. We dont know how much longer we can withstand the nothing", "mountain")</code> should return false.'');'
  - text: '<code>confirmEnding("Abstraction", "action")</code> should return true.'
    testString: 'assert(confirmEnding("Abstraction", "action") === true, ''<code>confirmEnding("Abstraction", "action")</code> should return true.'');'
  - text: Do not use the built-in method <code>.endsWith()</code> to solve the challenge.
    testString: 'assert(!(/\.endsWith\(.*?\)\s*?;?/.test(code)) && !(/\[''endsWith''\]/.test(code)), ''Do not use the built-in method <code>.endsWith()</code> to solve the challenge.'');'

Challenge Seed

function confirmEnding(str, target) {
  // "Never give up and good luck will find you."
  // -- Falcor
  return str;
}

confirmEnding("Bastian", "n");

Solution

function confirmEnding(str, target) {
  return str.substring(str.length - target.length) === target;
}

confirmEnding("Bastian", "n");