source file name: Armstrong1.CPP 

#include<stdio.h>

#include<conio.h>

#include<iostream.h>

int  main()

{

int n,d;

int sum=0,temp;

clrscr();

cout<<"\n enter any 3 digit number: ";

cin>>n;

temp=n;

while(n>0)

{

d=n%10;

sum=sum+(d*d*d);

n=n/10;

}

if(sum==temp)

cout<<"\n given no is Armstrong no ";

else

cout<<"\n given no is not Armstrong no ";


return 0;

}

output: