Generate all combinations of supplied words in JavaScript

We are required to write a JavaScript function that takes in an array of strings. The function should then generate and return all possible combinations of the strings of the array.

Example

The code for this will be −

const arr = ['a', 'b', 'c', 'd'];
const permutations = (len, val, existing) => {
   if(len==0){
      res.push(val);
      return;
   }
   for(let i=0; i<arr.length; i++){
      // so that we do not repeat the item, using an array here makes it
      O(1) operation
      if(!existing[i]){
         existing[i] = true;
         permutations(len−1, val+arr[i], existing);
         existing[i] = false;
      }
   }
}
let res = [];
const buildPermuations = (arr = []) => {
   for(let i=0; i < arr.length; i++){
      permutations(arr.length−i, "", []);
   }
};
buildPermuations(arr);
console.log(res);

Example

And the output in the console will be −

[
   'abcd', 'abdc', 'acbd', 'acdb', 'adbc', 'adcb',
   'bacd', 'badc', 'bcad', 'bcda', 'bdac', 'bdca',
   'cabd', 'cadb', 'cbad', 'cbda', 'cdab', 'cdba',
   'dabc', 'dacb', 'dbac', 'dbca', 'dcab', 'dcba',
   'abc', 'abd', 'acb', 'acd', 'adb', 'adc',
   'bac', 'bad', 'bca', 'bcd', 'bda', 'bdc',
   'cab', 'cad', 'cba', 'cbd', 'cda', 'cdb',
   'dab', 'dac', 'dba', 'dbc', 'dca', 'dcb',
   'ab', 'ac', 'ad', 'ba', 'bc', 'bd',
   'ca', 'cb', 'cd', 'da', 'db', 'dc',
   'a', 'b', 'c', 'd'
]

AmitDiwan

Published on 21-Nov-2020 09:29:10

• Related Questions & Answers
• Python - Generate all possible permutations of words in a Sentence
• All combinations of sums for array in JavaScript
• C++ Program to Generate All Possible Combinations of a Given List of Numbers
• Generate all combinations of a specific size from a single set in PHP
• Reverse all the words of sentence JavaScript
• How to get all combinations of some arrays in JavaScript?
• C++ Program to Generate All Possible Combinations Out of a,b,c,d,e
• Find all substrings combinations within arrays in JavaScript
• JavaScript function that generates all possible combinations of a string
• Algorithm to get the combinations of all items in array JavaScript
• Print all combinations of factors in C++
• Finding all possible combinations from an array in JavaScript
• Print all combinations of balanced parentheses in C++
• All pair combinations of 2 tuples in Python
• Replace all occurrence of specific words in a sentence based on an array of words in JavaScript