Strong Number

Medium Numbers

A strong number equals the sum of the factorials of its digits (e.g. 145 = 1! + 4! + 5!).

Sample input

145

Sample output

true

Solution

import math

n = 145
total = sum(math.factorial(int(d)) for d in str(n))
print(total == n)

function factorial(x) {
  let f = 1;
  for (let i = 2; i <= x; i++) f *= i;
  return f;
}

const n = 145;
let total = 0;
for (const d of String(n)) total += factorial(Number(d));
console.log(total === n);

public class Main {
    static int factorial(int x) {
        int f = 1;
        for (int i = 2; i <= x; i++) f *= i;
        return f;
    }

    public static void main(String[] args) {
        int n = 145, total = 0;
        for (char c : String.valueOf(n).toCharArray()) {
            total += factorial(c - '0');
        }
        System.out.println(total == n);
    }
}

fun factorial(x: Int): Int {
    var f = 1
    for (i in 2..x) f *= i
    return f
}

fun main() {
    val n = 145
    var total = 0
    for (c in n.toString()) {
        total += factorial(c - '0')
    }
    println(total == n)
}

func factorial(_ x: Int) -> Int {
    var f = 1
    if x >= 2 {
        for i in 2...x { f *= i }
    }
    return f
}

let n = 145
var total = 0
for c in String(n) {
    total += factorial(Int(String(c))!)
}
print(total == n)

int factorial(int x) {
  int f = 1;
  for (int i = 2; i <= x; i++) f *= i;
  return f;
}

void main() {
  int n = 145;
  int total = 0;
  for (var d in n.toString().split('')) {
    total += factorial(int.parse(d));
  }
  print(total == n);
}

#include <iostream>
#include <string>
using namespace std;

int factorial(int x) {
    int f = 1;
    for (int i = 2; i <= x; i++) f *= i;
    return f;
}

int main() {
    int n = 145, total = 0;
    for (char c : to_string(n)) {
        total += factorial(c - '0');
    }
    cout << (total == n ? "true" : "false") << endl;
    return 0;
}

#include <stdio.h>

int factorial(int x) {
    int f = 1;
    for (int i = 2; i <= x; i++) f *= i;
    return f;
}

int main() {
    int n = 145, temp = n, total = 0;
    while (temp > 0) {
        total += factorial(temp % 10);
        temp /= 10;
    }
    printf("%s\n", total == n ? "true" : "false");
    return 0;
}