Data structure:Using Java, 1. Read all words from a list of words and add them to a map whose keys arethe phone keypad spellings of the word, and whose values are sets of wordswith the same code. For example, 26337 is mapped to the set {"Andes","coder", "codes", ...}. Then keep prompting the user for numbers and printout all words in the dictionary that can be spelled with that number. In yoursolution, use a map that maps letters to digits.

import java.io.File; import java.util.*; public class PhoneKeypad { public static void main(String[] args){ String phNumber = ""; String output = ""; HashMap<String, String> map = new HashMap<>(); try{ Scanner sc = new Scanner(new File("C:\\Users\\Mirchi\\Desktop\\Tester.java")); while(sc.hasNext()){ phNumber = sc.next(); output = ""; for(int i = 0 ; i < phNumber.length() ; i++){ char ch = Character.toUpperCase(phNumber.charAt(i)); if(Character.isLetter(ch)){ int digit = getNumber(ch); output = output + digit; } else{ output = output + ch; } } //System.out.println(phNumber+" "+output); map.put(phNumber, output);} Scanner userInput=new Scanner(System.in); System.out.print("Enter number to find keypad strings of input file :"); String str=userInput.next(); int flag=0; for (HashMap.Entry<String,String> entry : map.entrySet()) { if(str.equalsIgnoreCase(entry.getValue())){ System.out.println(entry.getKey()); flag=1; } } if(flag==0) System.out.println("no matchings found"); }catch(Exception e){System.out.println("input file is missing");} } public static int getNumber(char upperCaseLetter){ if(upperCaseLetter == 'A' || upperCaseLetter =='B'|| upperCaseLetter == 'C') return 2; else if(upperCaseLetter == 'D' || upperCaseLetter =='E' || upperCaseLetter == 'F') return 3; else if(upperCaseLetter == 'G' || upperCaseLetter =='H' || upperCaseLetter == 'I') return 4; else if(upperCaseLetter == 'J' || upperCaseLetter== 'K' || upperCaseLetter == 'L') return 5; else if(upperCaseLetter == 'M' || upperCaseLetter =='N' || upperCaseLetter == 'O') return 6; else if(upperCaseLetter == 'P' || upperCaseLetter =='Q' || upperCaseLetter == 'R'||upperCaseLetter == 'S') return 7; else if( upperCaseLetter =='T' || upperCaseLetter == 'U'||upperCaseLetter == 'V' ) return 8; else if( upperCaseLetter =='W' ||upperCaseLetter =='X'|| upperCaseLetter == 'Y' || upperCaseLetter == 'Z') return 9; else return 0; } }