C program to check for an Armstrong number

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The below program checks for an Armstrong number using a loop. The C printf statement is used to output the result on the screen. A number is called as an Armstrong number if the sum of the cubes of its digits is equal to the number itself.

Armstrong Number:
abc = (a*a*a) + (b*b*b) + (c*c*c)

Example: 0, 1, 153, 371, 407, etc.

C program to check for an Armstrong number

#include <stdio.h>
 
void main()
{
 
int num,x;
int sum = 0;    
 
printf("Enter a number:");    
scanf("%d",&num);
int i = num;
 
while(i!=0)  
{  
x = i%10;  
sum= sum + x*x*x;  
i = i/10;  
}
 
if(num==sum)  
{  
printf ("%d is an Armstrong Number.", num);  
}  
 
else  
{  
printf ("%d is not an Armstrong Number.", num);  
}  
}

Output

Enter a number:407
407 is an Armstrong Number.