Question

In java

6. Device Name System

Suggested Problem Name: Device Name System

Suggested Function Name: deviceNamesSystem

Create unique device names to be used in a residential loT (Internet of Things) system. If a device name already exists in the system, an integer number is added at the end of the name to make it unique. The integer added starts with 1 and is incremented by 1 for each new request of an existing device name. Given a list of device name requests, process all requests and return an array of the corresponding unique device names.

Example

n=6

devicenames = ['switch', 'tv', 'switch', 'tv', 'switch', 'tv']

Function Description

Complete the function deviceNamesSystem in the editor below.

deviceNamesSystem has the following parameter(s):

string devicenames/n]: an array of device name strings in the order requested.

Returns

string [n] : an array of string usernames in the order assigned

Answer 1

//required method, copy and paste wherever you want

public static String[] deviceNamesSystem(String deviceNames[]) {

      // creating an array of same size to keep the results

      String uniqueNames[] = new String[deviceNames.length];

      // looping from i=0 to deviceNames.length-1

      for (int i = 0; i < deviceNames.length; i++) {

            // fetching device name at index i

            String name = deviceNames[i];

            // initially assuming this is not a duplicate value

            boolean duplicate = false;

            // looping and checking if this value exist previously

            for (int j = 0; j < i; j++) {

                  if (uniqueNames[j].equals(name)) {

                        // exists. setting duplicate to true and exiting inner loop

                        duplicate = true;

                        break;

                  }

            }

            // if this is no duplicate, adding unchanged name to uniqueNames

            // array

            if (!duplicate) {

                  uniqueNames[i] = name;

            } else {

                  // otherwise starting with id=1

                  int id = 1;

                  boolean exists = true;

                  // looping as long as exists is true

                  while (exists) {

                        // initially assuming device with this name does not exist

                        // already

                        exists = false;

                        // looping and checking the previous elements in uniqueNames

                        // for devicename: name+id (here + is for concatenation)

                        for (int j = 0; j < i; j++) {

                              if (uniqueNames[j].equals(name + id)) {

                                    // found, setting exists to true

                                    exists = true;

                                    // moving to next id

                                    id++;

                                    // exiting inner loop

                                    break;

                              }

                        }

                  }

                  // after the loop, adding name+id to the uniqueNames array

                  // example: if name is "switch", and id is 7, name+id returns

                  // "switch7"

                  uniqueNames[i] = name + id;

            }

      }

      //returning the array

      return uniqueNames;

}

Answer 2

String a[] = {"a","a","b","c","a","d","b","b","b"};
        String b[] = new String[a.length];
        int cnt = 0;
        for (int i = 0; i < a.length; i++) {
            cnt = 0;
            for (int j = 0; j < a.length; j++) {
                if(a[i] == a[j]) {
                     cnt++;
                     if(cnt-1 == 0) {
                         b[j] = a[i];
                     }else {
                         b[j] = a[i]+ (cnt-1);
                     }            
                }
            }
        }
        System.out.println(Arrays.asList(b));

Answer 3

public static List<String> deviceNamesSystem(List<String> devicenames) {

            

            List<String> res=new ArrayList<>();

            

            HashMap<String,Integer> map=new HashMap<>();

            

            for(int i=0;i<devicenames.size();i++){

                    if(map.containsKey(devicenames.get(i))){

                            

                            String temp=devicenames.get(i)+""+map.get(devicenames.get(i));

                            res.add(temp);

                            map.put(devicenames.get(i), map.get(devicenames.get(i)) + 1);

                    }

                    else{

                            res.add(devicenames.get(i));

                            map.put(devicenames.get(i), 1);

                    }

                    

                    

            }

            

            

            

            

            return res;

}