Skip to main content

17 Letter Combinations of a Phone Number Leetcode Problem Javascript Solution

Letter Combinations of a Phone Number
Medium
Given a string containing digits from 2-9 inclusive, return all possible letter combinations that the number could represent.
A mapping of digit to letters (just like on the telephone buttons) is given below. Note that 1 does not map to any letters.
Example:
Input: "23"
Output: ["ad", "ae", "af", "bd", "be", "bf", "cd", "ce", "cf"].
Note:
Although the above answer is in lexicographical order, your answer could be in any order you want.
RUN THE CODE HERE: https://repl.it/@VinitKhandelwal/telephone-text-javascript-leetcode

For people looking for solution in Javascript, here is a recursive solution. for other languages, please convert the code

const group = [];
result = [];
let numstr = "";
var letterCombinations = function(num) {
  numstr = num.toString();
  const letters = [,,['a','b','c'],['d','e','f'],['g','h','i'],['j','k','l'],['m','n','o'],['p','q','r','s'],['t','u','v'],['w','x','y','z']];
  for (let i=0; i<numstr.length; i++) {
    group.push(letters[parseInt(numstr[i])]);
  }
  wordMaker(num, 0, "");
  return result;
}

const wordMaker = (num, n, w) => {
  for (let i=0; i<group[n].length; i++) {
    if (n === group.length-1) {
      result.push(w + group[n][i])
    }
    else {
      wordMaker(num, n+1, w + group[n][i]);
    }
  }
}

Test Input

console.log(letterCombinations(23));

Output

[ 'ad', 'ae', 'af', 'bd', 'be', 'bf', 'cd', 'ce', 'cf' ]


Comments

Post a Comment

Popular posts from this blog

Python - List - Append, Count, Extend, Index, Insert, Pop, Remove, Reverse, Sort

🐍 Advance List List is widely used and it's functionalities are heavily useful. Append Adds one element at the end of the list. Syntax list1.append(value) Input l1 = [1, 2, 3] l1.append(4) l1 Output [1, 2, 3, 4] append can be used to add any datatype in a list. It can even add list inside list. Caution: Append does not return anything. It just appends the list. Count .count(value) counts the number of occurrences of an element in the list. Syntax list1.count(value) Input l1 = [1, 2, 3, 4, 3] l1.count(3) Output 2 It returns 0 if the value is not found in the list. Extend .count(value) counts the number of occurrences of an element in the list. Syntax list1.extend(list) Input l1 = [1, 2, 3] l1.extend([4, 5]) Output [1, 2, 3, 4, 5] If we use append, entire list will be added to the first list like one element. Extend, i nstead of considering a list as one element, it joins the two lists one after other. Append works in the following way. Input l1 = [1, 2, 3] l1.append([4, 5]) Output...
Post a Comment
Read more

Difference between .exec() and .execPopulate() in Mongoose?

Here I answer what is the difference between .exec() and .execPopulate() in Mongoose? .exec() is used with a query while .execPopulate() is used with a document Syntax for .exec() is as follows: Model.query() . populate ( 'field' ) . exec () // returns promise . then ( function ( document ) { console . log ( document ); }); Syntax for .execPopulate() is as follows: fetchedDocument . populate ( 'field' ) . execPopulate () // returns promise . then ( function ( document ) { console . log ( document ); }); When working with individual document use .execPopulate(), for model query use .exec(). Both returns a promise. One can do without .exec() or .execPopulate() but then has to pass a callback in populate.
1 comment
Read more

Python Class to Calculate Distance and Slope of a Line with Coordinates as Input

🐍  Can be run on Jupyter Notebook #CLASS DESIGNED TO CREATE OBJECTS THAT TAKES COORDINATES AND CALCULATES DISTANCE AND SLOPE class Line:     def __init__(self,coor1,coor2):         self.coor1=coor1         self.coor2=coor2 #FUNCTION CALCULATES DISTANCE     def distance(self):         return ((self.coor2[0]-self.coor1[0])**2+(self.coor2[1]-self.coor1[1])**2)**0.5 #FUNCTION CALCULATES SLOPE         def slope(self):         return (self.coor2[1]-self.coor1[1])/(self.coor2[0]-self.coor1[0]) #DEFINING COORDINATES coordinate1 = (3,2) coordinate2 = (8,10) #CREATING OBJECT OF LINE CLASS li = Line(coordinate1,coordinate2) #CALLING DISTANCE FUNCTION li.distance() #CALLING SLOPE FUNCTION li.slope()
Post a Comment
Read more