Skip to content
Related Articles

Related Articles

Improve Article

Demlo number (Square of 11…1)

  • Difficulty Level : Easy
  • Last Updated : 30 Apr, 2021

Given a number of the form 11..1 such that number of digits in it is smaller than 10, find square of the number.
Examples: 
 

Input : 111111
Output : 12345654321

Input : 1111
Output : 1234321

 

Squares of 11…1 (where length is smaller than 10) are called Demlo numbers. A demlo number is number which consist of 1, 2, 3….n, n-1, n-2, …..1. 
Demlo numbers are: 
 

1 = 1
11 * 11 = 121
111 * 111 = 12321
1111 * 1111 = 1234321

To find demlo number, first we find append n numbers which are increasing and then append numbers which are decreasing.
 

C++




// CPP program to print DemloNumber
#include <bits/stdc++.h>
using namespace std;
 
// To return demlo number. This function assumes
// that the length of str is smaller than 10.
string printDemlo(string str)
{
    int len = str.length();
    string res = "";
 
    // Add numbers to res upto size
    // of str and then add number
    // reverse to it
    for (int i = 1; i <= len; i++)
        res += char(i + '0');
 
    for (int i = len - 1; i >= 1; i--)
        res += char(i + '0');
 
    return res;
}
 
// Driver program to test printDemlo()
int main()
{
    string str = "111111";
    cout << printDemlo(str);
    return 0;
}

Java




// Java program to print DemloNumber
public class Main {
 
    // To return demlo number. This function assumes
    // that the length of str is smaller than 10.
    static String printDemlo(String str)
    {
        int len = str.length();
        String res = "";
 
        // Add numbers to res upto size
        // of str and then add number
        // reverse to it
        for (int i = 1; i <= len; i++)
            res += Integer.toString(i);
 
        for (int i = len - 1; i >= 1; i--)
            res += Integer.toString(i);
 
        return res;
    }
 
    // Driver program to test printDemlo()
    public static void main(String[] args)
    {
        String str = "111111";
        System.out.println(printDemlo(str));
    }
}

Python




# Python program to print Demlo Number
 
# To return demlo number
# Length of s is smaller than 10
def printDemlo(s):
    l = len(s)
    res = ""
     
    # Add numbers to res upto size
    # of s then add in reverse
     
    for i in range(1,l+1):
        res = res + str(i)
     
    for i in range(l-1,0,-1):
        res = res + str(i)
     
    return res
     
 
# Driver Code
s = "111111"   
print printDemlo(s)
 
# Contributed by Harshit Agrawal

C#




// C# program to print DemloNumber
using System;
public class GFG {
 
    // To return demlo number. This function assumes
    // that the length of str is smaller than 10.
    static String printDemlo(String str)
    {
        int len = str.Length;
        String res = "";
 
        // Add numbers to res upto size
        // of str and then add number
        // reverse to it
        for (int i = 1; i <= len; i++)
            res += i.ToString();
 
        for (int i = len - 1; i >= 1; i--)
            res += i.ToString();
 
        return res;
    }
 
    // Driver program to test printDemlo()
    public static void Main()
    {
        String str = "111111";
        Console.WriteLine(printDemlo(str));
    }
}
// This code is contributed by mits

PHP




<?php
// PHP program to print DemloNumber
 
// To return demlo number. This function
// assumes that the length of str is
// smaller than 10.
function printDemlo($str)
{
    $len = strlen($str);
    $res = "";
 
    // Add numbers to res upto size
    // of str and then add number
    // reverse to it
    for ($i = 1; $i <= $len; $i++)
        $res .= chr($i + 48);
 
    for ($i = $len - 1; $i >= 1; $i--)
        $res .= chr($i + 48);
 
    return $res;
}
 
// Driver Code
$str = "111111";
echo printDemlo($str);
 
// This code is contributed by mits
?>

Javascript




<script>
 
// Javascript program to print DemloNumber
 
    // To return demlo number. This function assumes
    // that the length of str is smaller than 10.
    function printDemlo(str)
    {
        let len = str.length;
        let res = "";
   
        // Add numbers to res upto size
        // of str and then add number
        // reverse to it
        for (let i = 1; i <= len; i++)
            res += i.toString();
   
        for (let i = len - 1; i >= 1; i--)
            res += i.toString();
   
        return res;
    }
     
// driver program
        let str = "111111";
        document.write(printDemlo(str));
   
  // This code is contributed by susmitakundugoaldanga.
</script>

Output: 
 



12345654321

This article is contributed by nuclode. If you like GeeksforGeeks and would like to contribute, you can also write an article using write.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.
 

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.  To complete your preparation from learning a language to DS Algo and many more,  please refer Complete Interview Preparation Course.

In case you wish to attend live classes with experts, please refer DSA Live Classes for Working Professionals and Competitive Programming Live for Students.




My Personal Notes arrow_drop_up
Recommended Articles
Page :