Given an array arr[] consisting of N integers, the task is to check if the number formed by concatenating all the array elements is a Harshad number or not.
Examples:
Input: arr[] = { 1, 35, 69, 60 }
Output: Yes
Explanation:
The number formed by concatenating array elements is “1356960”.
Sum of digits of the number = 1 + 3 + 5 + 6 + 9 + 6 + 0 = 30.
Since, the number is divisible by sum of its digits, the number is a “Harshad number”.Input: arr[] = {1, 563, 9, 59, 7, 8 }
Output: No
Explanation:
The number formed by concatenating array elements is “156395978”, which is not divisible by its sum of digits.
Therefore, the number formed is not a a Harshad number.
Approach: The idea is to convert all array elements to their equivalent strings and concatenate those strings. Follow the steps below to solve the problem:
- Traverse the array arr[] and convert each array element to its equivalent string.
- Concatenate all the strings in a variable, say S.
- Initialize a variable, say sum, to store the sum of digits of the generated number.
- Traverse the string S and update sum as sum += int (s[i]).
- Initialize a variable, say N = 0, to store the number formed by joining all the characters of the string S mod sum.
- Traverse the string S and update N as N = (N * 10 + int (S[i])) % sum.
- Print Yes, if N = 0.
- Otherwise, print No.
Below is the implementation of the above approach:
C++
// CPP implementation// of above approach#include<bits/stdc++.h>using namespace std;// Function to check whether n// is a harshad number or notint checkHarshad(string n){ // Stores the sum of digits int sum = 0; // Stores the remainder int N = 0; // Increment sum for (int c = 0; c < n.length(); c++) sum += (n); for (int c = 0; c < n.length(); c++) { N = N + (N * 10 + (n)); N %= sum; } return (N != 0);}// Function to check if conctenation// of elements from the array arr[]// is a harshad number or notbool combineArray(vector<int> lis){ // Stores the concatenated number string st = ""; // Traverse the array for(auto el: lis) { // Concatenate the string st += to_string(el); } if(checkHarshad(st)) return true; else return false;}// Driver Codeint main(){ // Input vector<int>arr{1, 35, 69, 60}; // Function call to check if // concatenation of elements of // arr[] is a harshad number if(combineArray(arr)) cout << "Yes"; else cout << "No";}// This code is contributed by ipg2016107. |
Java
/*package whatever //do not write package name here */import java.io.*;import java.util.ArrayList;class GFG { // Function to check whether n // is a harshad number or not public static boolean checkHarshad(String n) { // Stores the sum of digits int sum = 0; // Stores the remainder int N = 0; // Increment sum for (int c = 0; c < n.length(); c++) { sum += Character.getNumericValue(n.charAt(c)); } for (int c = 0; c < n.length(); c++) { N = N + (N * 10 + (Character.getNumericValue( n.charAt(c)))); N %= sum; } if (N == 0) { return true; } return false; } // Function to check if conctenation // of elements from the array arr[] // is a harshad number or not public static boolean combineArray(ArrayList<Integer> list) { // Stores the concatenated number String st = ""; // Traverse the array for (int i = 0; i < list.size(); i++) { // Concatenate the string st += Integer.toString(list.get(i)); } if (checkHarshad(st)) { return true; } return false; } // Driver Code public static void main(String[] args) { // Input ArrayList<Integer> list = new ArrayList<>(); list.add(1); list.add(35); list.add(69); list.add(60); // Function call to check if // concatenation of elements of // arr[] is a harshad number if (combineArray(list)) System.out.println("Yes"); else System.out.println("No"); }}// This code is contributed by aditya7409 |
Python3
# Python implementation# of above approach# Function to check whether n# is a harshad number or notdef checkHarshad(n): # Stores the sum of digits sum = 0 # Stores the remainder N = 0 # Increment sum for c in n: sum += int(c) for c in n: N = N + (N*10+int(c)) N %= sum return N == 0# Function to check if conctenation# of elements from the array arr[]# is a harshad number or notdef combineArray(lis): # Stores the concatenated number string="" # Traverse the array for el in lis: # Convert to equivalent string el = str(el) # Concatenate the string string = string + el if(checkHarshad(string)): return True else: return False# Driver Code# Inputarr=[1, 35, 69, 60]# Function call to check if# concatenation of elements of# arr[] is a harshad numberif(combineArray(arr)): print("Yes")else: print("No") |
C#
// C# program for the above approachusing System;using System.Collections.Generic;class GFG{ // Function to check whether n // is a harshad number or not public static bool checkHarshad(string n) { // Stores the sum of digits int sum = 0; // Stores the remainder int N = 0; // Increment sum for (int c = 0; c < n.Length; c++) { sum += (int)Char.GetNumericValue(n); } for (int c = 0; c < n.Length; c++) { N = N + (N * 10 + (int)(Char.GetNumericValue( n))); N %= sum; } if (N == 0) { return true; } return false; } // Function to check if conctenation // of elements from the array arr[] // is a harshad number or not static bool combineArray(List<int> list) { // Stores the concatenated number string st = ""; st += string.Join("", list); if (checkHarshad(st)) { return true; } return false; }// Driver codestatic void Main(){ List<int> list = new List<int>(); list.Add(1); list.Add(35); list.Add(69); list.Add(60); // Function call to check if // concatenation of elements of // arr[] is a harshad number if (combineArray(list)) Console.WriteLine("Yes"); else Console.WriteLine("No");}}// This code is contributed susmitakundugoaldanga. |
Yes
Time Complexity: O(N)
Auxiliary Space: O(N)
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