# Golang : Test if an input is an Armstrong number example

An Armstrong number of three digits is an integer such that the sum of the cubes of its digits is equal to the number itself.

For example, 371 is an Armstrong number since `3**3 + 7**3 + 1**3 = 371.`

Below is an example code to test if a given input is an Armstrong number or not.

`````` package main

import (
"fmt"
)

func main() {

var rightMost, num int
var cubicSum int = 0
var tempNum int = 0

fmt.Print("Enter a 3 digits number : ")
fmt.Scanf("%d", &num)

tempNum = num

// get the right most digit
for {
rightMost = tempNum % 10
cubicSum += rightMost * rightMost * rightMost

// update the input digit minus the processed rightMost
tempNum /= 10

if tempNum == 0 {
// break the for loop
break
}
}

if num == cubicSum {
fmt.Println(num, "is an Armstrong number!")
} else {
fmt.Println(num, "is NOT an Armstrong number!")
}
}
``````

Sample output:

\$ go run armstrong.go

Enter a 3 digits number : 371

371 is an Armstrong number!

\$ go run armstrong.go

Enter a 3 digits number : 157

157 is NOT an Armstrong number!

\$ go run armstrong.go

Enter a 3 digits number : 153

153 is an Armstrong number!

References:

http://pages.mtu.edu/~shene/COURSES/cs201/NOTES/chap04/arms.html

#### See also : Golang : Test a slice of integers for odd and even numbers

##### By Adam Ng

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