Program to print all Kaprekar numbers between 1 to 100

Java Program

public class Kaprekar_Number {  
    static boolean kaprekar(int n)   
    {   
        if (n == 1)   
           return true;   
        int sq_n = n * n;   
        int count_digits = 0;   
        while (sq_n != 0)   
        {   
            count_digits++;   
            sq_n /= 10;   
        }   
        sq_n = n*n;   
        for (int r_digits=1; r_digits<count_digits; r_digits++)   
        {   
             int eq_parts = (int) Math.pow(10, r_digits);   
            if (eq_parts == n)   
                continue;   
             int sum = sq_n/eq_parts + sq_n % eq_parts;   
             if (sum == n)   
               return true;   
        }   
        return false;   
    }       
    public static void main (String[] args)   
    {   
       for (int i=1; i<100; i++)   
            if (kaprekar(i))   
                 System.out.print(i + " ");   
    }   
}   

Output:

9  10  45  55  99 

Python Program

def print_Kaprekar_nums(start, end):  
   for i in range(start, end ):  
      sqr = i ** 2  
      digits = str(sqr)  
  
      length = len(digits)  
      for x in range(1, length):  
         left = int("".join(digits[:x]))  
         right = int("".join(digits[x:]))  
         if (left + right) == i:  
            print("%s "%(str(i)), end = " ");  
  
print_Kaprekar_nums(1, 100)  

Output:

9  10  45  55  99

C Program

# include <stdio.h>  
# include <string.h>  
# include <stdbool.h>  
# include <math.h>  
bool kaprekar(int n)   
    {   
        if (n == 1)   
           return true;   
        int sq_n = n * n;   
        int count_digits = 0;   
        while (sq_n != 0)   
        {   
            count_digits++;   
            sq_n /= 10;   
        }   
        sq_n = n*n;   
        for (int r_digits=1; r_digits<count_digits; r_digits++)   
        {   
             int eq_parts = (int) pow(10, r_digits);   
            if (eq_parts == n)   
                continue;   
             int sum = sq_n/eq_parts + sq_n % eq_parts;   
             if (sum == n)   
               return true;   
        }   
        return false;   
    }    
  
  
int main()  
{  
for (int i=1; i<100; i++) {  
if (kaprekar(i))   
printf("%d  ",i );   
}  
return 0;  
}  

Output:

9  10  45  55  99 

C# Program:

using System;  
public class Kaprekar {   
          static bool iskaprekar(int n)   
    {   
        if (n == 1)   
            return true;   
    int sq_n = n * n;   
        int count_digits = 0;   
        while (sq_n != 0) {   
            count_digits++;   
            sq_n /= 10;   
        }   
        sq_n = n * n;    
        for (int r_digits = 1; r_digits < count_digits; r_digits++)   
        {   
            int eq_parts = (int)Math.Pow(10, r_digits);   
            if (eq_parts == n)   
                continue;   
      int sum = sq_n / eq_parts + sq_n % eq_parts;   
            if (sum == n)   
                return true;   
        }   
           return false;   
    }    
    public static void Main()   
    {   
        for (int i = 1; i < 100; i++)   
            if (iskaprekar(i))   
                Console.Write(i + " ");   
    }   
}  

Output:

9  10  45  55  99

PHP program

<?php   
function kap($n)   
{   
    if ($n == 1)   
    return true;   
    $sq_n = $n * $n;   
    $count_digits = 0;   
    while ($sq_n)   
    {   
        $count_digits++;   
        $sq_n = (int)($sq_n / 10);   
    }   
    
    $sq_n1 = $n * $n;   
    for ($r_digits = 1;    
         $r_digits < $count_digits;    
         $r_digits++)   
    {   
        $eq_parts = pow(10, $r_digits);   
       if ($eq_parts == $n)   
            continue;   
    
        $sum = (int)($sq_n1 / $eq_parts) +   
                     $sq_n1 % $eq_parts;   
        if ($sum == $n)   
        return true;   
    }   
    return false;   
}   
  for ($i = 1; $i < 100; $i++)   
    if (kap($i))   
        echo $i . " ";   
?>  

Output:

9  10  45  55  99