This is a C Program to check whether a given number is armstrong.

This C Program checks whether a given number is armstrong number.

An Armstrong number is an n-digit base b number such that the sum of its (base b) digits raised to the power n is the number itself. Hence 153 because 1^{3} + 5^{3} + 3^{3} = 1 + 125 + 27 = 153.

Here is source code of the C Program to check whether a given number is armstrong number.

The C program is successfully compiled and run on a Linux system. The program output is also shown below.

/* * C Program to Check whether a given Number is Armstrong */ #include <stdio.h> #include <math.h> void main() { int number, sum = 0, rem = 0, cube = 0, temp; printf ("enter a number"); scanf("%d", &number); temp = number; while (number != 0) { rem = number % 10; cube = pow(rem, 3); sum = sum + cube; number = number / 10; } if (sum == temp) printf ("The given no is armstrong no"); else printf ("The given no is not a armstrong no"); }

In this C program, we are reading the integer value using ‘number’ variable. An Armstrong number is an n-digit base b number, such that the sum of its digits raised to the power n is the number itself. Hence, 153 because 1^{3} + 5^{3} + 3^{3} = 1 + 125 + 27 = 153.

Using while loop checks the value of ‘number’ variable is not equal to 0. If the condition is true, execute the iteration of the loop. The ‘rem’ variable is used to compute the modulus of the value of ‘number’ variable by 10 and ‘cube’ variable is used to compute the cube of the value of ‘rem’ variable using pow().

Then ‘sum’ variable is used to compute the summation of the value of ‘sum’ variable with the value of ‘cube’ variable. The If-else condition statement is used to check both the value of ‘sum’ variable and the value of ‘temp’ variable are equal. If the condition is true, then it will print Armstrong number. Otherwise, it will execute the else condition statement and print not Armstrong number.

Output: $ cc pgm41.c -lm $ a.out enter a number370 The given no is armstrong no $ a.out enter a number1500 The given no is not a armstrong no

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