JavaScript Machine Problems

JavaScript Machine Problems by Myca Joanne M. Faeldonia

Main Machine Problems

Machine Problem 1: ReplaceAll

Replace all occurrences of space with no space.

Input:

Machine Problem 2: SearchWord

Check if a word exists in the given sentence.

Sentence:

Word:

Machine Problem 3: ReplaceWord

Replace the first occurrence of a word in a sentence.

Sentence:

Old Word:

New Word:

Machine Problem 4: CountCharacters

Count the number of characters (excluding leading and trailing spaces).

Input:

Machine Problem 5: EmailCheck

Check if the input is a valid email (must contain @).

Email:

Additional String Problems

Reverse String

Input:

Count Words

Sentence:

Capitalize First Letter

Input:

Capitalize Each Word

Sentence:

Check Palindrome

Input:

Extract First N Characters

String:

Extract Last N Characters

String:

Count Specific Character

String:

Character:

Convert Case

Input:

Check Starts/Ends With

String:

Prefix/Suffix:

Find Index of Substring

String:

Search:

Repeat String

String:

Times:

Pad String

String:

Length:

Character:

Array Problems

Enter numbers separated by commas (e.g., 1,2,3,4)

Sum of Array

Array:

Average of Array

Array:

Find Maximum

Array:

Find Minimum

Array:

Filter Even Numbers

Array:

Filter Odd Numbers

Array:

Double Each Element

Array:

Remove Duplicates

Array:

Sort Array Ascending

Array:

Sort Array Descending

Array:

Number Problems

Check Even or Odd

Number:

Check Sign

Number:

Factorial

Number:

Fibonacci Series

Count:

Check Prime

Number:

Random Number in Range

Min:

Max:

String Method Quick Reference

Method	Purpose	Example
`trim()`	Remove leading/trailing spaces	`" hi ".trim()` → `"hi"`
`replace(a, b)`	Replace first occurrence	`"aa".replace("a", "b")` → `"ba"`
`replaceAll(a, b)`	Replace all occurrences	`"aa".replaceAll("a", "b")` → `"bb"`
`includes(s)`	Check if contains	`"hello".includes("ell")` → `true`
`indexOf(s)`	Find index	`"hello".indexOf("l")` → `2`
`length`	Get length	`"hello".length` → `5`
`toUpperCase()`	Convert to uppercase	`"hi".toUpperCase()` → `"HI"`
`toLowerCase()`	Convert to lowercase	`"HI".toLowerCase()` → `"hi"`
`split(sep)`	Split to array	`"a,b".split(",")` → `["a","b"]`
`slice(start, end)`	Extract portion	`"hello".slice(0, 2)` → `"he"`
`charAt(i)`	Get character at index	`"hello".charAt(0)` → `"h"`
`startsWith(s)`	Check start	`"hello".startsWith("he")` → `true`
`endsWith(s)`	Check end	`"hello".endsWith("lo")` → `true`
`repeat(n)`	Repeat string	`"hi".repeat(3)` → `"hihihi"`
`padStart(n, c)`	Pad start	`"5".padStart(3, "0")` → `"005"`
`padEnd(n, c)`	Pad end	`"5".padEnd(3, "0")` → `"500"`