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CPP program to check for an Armstrong number

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The below program checks for an Armstrong number using a loop. The CPP cout object 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.

Code:

#include <iostream.h>
using namespace std;
 
int main()  
{  
int num,x;
int sum = 0;    
 
cout << "Enter a number:";    
cin >> num;
int i = num;
 
while(i!=0)  
{  
x = i%10;  
sum= sum + x*x*x;  
i = i/10;  
}
 
if(num==sum)  
cout << num << " is an Armstrong Number.";  
else  
cout << num << " is not an Armstrong Number.";  
return 0;
}

Output

Enter a number:407
407 is an Armstrong Number.