Given a number we have to find whether number is armstrong or not.
So what is Armstrong number?
Armstrong Number is a number which is equal to the sum of cube of its digit.
for example-0,1,153,371 all are armstrong number.
Example:
input:1
output:true
input :9:
output:false
Logic:
Logic behind this question is to just find all the digit of number then calculate cube of all digits. then resultant output is armstrong number.
#include<iostream> using namespace std; int main() { int num; cout<<"Enter a number : "<<endl; cin>>num; int armstrong=0; int original_number=num; int pal=0; while(num>0) { int rem=num%10; armstrong+=rem*rem*rem; num=num/10; } if(armstrong==original_number) { cout<<"number is armstrong "<<endl; } else { cout<<"number is not armstrong"<<endl; } }
Output:
Enter a number : 371 number is armstrong
Time Complexity-O(N)
Space Complexity-0(1)