Automorphic Number Program in C

In this article, we will write a C Program for Automorphic Number. The following C programming topic is used in the program below.

• while loop
• if..else statement

A number is said to be an automorphic number if the square of the given number ends with the same digits as the number itself. Example: 25, 76, 376, etc.

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Automorphic Number Program in C

The C program to check automorphic number below takes the number from the user as input and checks accordingly.

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int main()
{
  int num;
  printf("Enter the number: ");
  scanf("%d", &num);

  int sqr, temp, last;
  int count = 0;

  sqr = num * num;
  temp = num;

  //Counting digits
  while (temp > 0)
  {
    count++;
    temp = temp / 10;
  }

  //calculation
  int den = floor(pow(10, count));
  last = sqr % den;

  //display
  if (last == num)
    printf("%d is an Automorphic number.", num);
  else
    printf("%d Not Automorphic number.", num);

  return 0;
}

Output:

Enter the number: 25
25 is an Automorphic number.

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