Unique Device Names

Problem Statement:

Create unique device names to be used in a residential IoT (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 display an array of the corresponding unique device names.

Constraints

• 1<=n<=10^4
• 1<=length of devicenames[i]<=20
• devicenames[i] contains only lowercase English letters in the range ASCII[a-z].

Input Format:

The first line contains an integer, n, denoting the size of the array.
Each line i of the n subsequent lines (where 0<=i<n) contains a string.

Output Format:

Display unique device names in n lines.

Sample Input:
6
switch
tv
switch
tv
switch
tv
Sample Output:
switch
tv
switch1
tv1
switch2
tv2

Solution in	C	JAVA	PYTHON

#include<stdio.h>
#include<string.h>

int main() {
    char devicenames[10][20],result[10][20];
    int n,i,j;
    scanf("%d\n",&n);
    for(i=0;i<n;i++){
        fgets(devicenames[i],20,stdin);
    }
    for(i=0;i<n;i++){
        devicenames[i][strlen(devicenames[i])-1]='\0';
        puts(devicenames[i]);
    }
    for(i=0;i<n;i++){
        int count=0;
        char buf[3];
        for(j=0;j<i;j++){
            if(strcmp(devicenames[i],devicenames[j])==0){
                count++;
            }
        }
        if(count==0){
            strcpy(result[i],devicenames[i]);
        }else{
            strcpy(result[i],devicenames[i]);
            sprintf(buf,"%d",count);
            strcat(result[i],buf);
        }
    }
    for(i=0;i<n;i++){
        puts(result[i]);
    }
    return 0;
}

import java.util.Scanner;

public class UniqueDeviceNames{
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        sc.nextLine();
        String deviceNames[] = new String[n];
        for(int i=0;i<n;i++){
            deviceNames[i] = sc.nextLine();
        }
        String uniqueDeviceNames[] = new String[n];
        for(int i=0;i<n;i++){
            int count = 0;
            for(int j=0;j<i;j++){
                if(deviceNames[i].equals(deviceNames[j])){
                    count++;
                }
            }
            if(count==0){
                uniqueDeviceNames[i] = deviceNames[i];
            }else{
                uniqueDeviceNames[i] = deviceNames[i] + String.valueOf(count);
            }
        }
        for(int i=0;i<n;i++){
            System.out.print(uniqueDeviceNames[i]);
            if(i<n-1){
                System.out.println();
            }
        }
    }
}

n = int(input())
devicenames = [input() for i in range(n)]
result = []
for i in range(len(devicenames)):
    name = devicenames[i]
    if name in result:
        num = devicenames[:i+1].count(devicenames[i])-1
        result.append(devicenames[i]+str(num))
    else:
        result.append(devicenames[i])
for device in result:
    print(device)

Input
6
switch
tv
switch
tv
switch
tv
Output
switch
tv
switch1
tv1
switch2
tv2