Digit fifth powers | Project Euler | Problem #30

URL to the problem page: https://projecteuler.net/problem=30

Surprisingly there are only three numbers that can be written as the sum of fourth powers of their digits:

1634 = 1⁴ + 6⁴ + 3⁴ + 4⁴
8208 = 8⁴ + 2⁴ + 0⁴ + 8⁴
9474 = 9⁴ + 4⁴ + 7⁴ + 4⁴

As 1 = 1⁴ is not a sum it is not included.

The sum of these numbers is 1634 + 8208 + 9474 = 19316.

Find the sum of all the numbers that can be written as the sum of fifth powers of their digits.

#include <iostream>

using namespace std;

long long int power(long long int a, long long int b) {

    long long int result = 1;

    for (int i = 0; i < b; i++) {

        result = result * a;

    }

    return result;

}

long long int finddigits(long long int a) {

    long long int counter = 1;

    while (a >= 10) {

        a /= 10;

        counter++;

    }

    return counter;

}

int main()

{

    long long int i, result = 0;

    for (i = 2; i < 10000000; i++) {

        long long int digitnumber = finddigits(i), sum = 0, j;

        long long int* digits = new long long int[digitnumber];

        for (j = digitnumber; j > 0; j--) {

            digits[j - 1] = (i % power(10, j)) / (power(10, (j - 1)));

        }

        for (j = 0; j < digitnumber; j++) {

            sum += power(digits[j], 5);

        }

        if (sum == i) {

            result += i;

        }

    }

    cout << endl << "Sum of all the numbers that can be written as the sum of fifth powers of their digits is  =  " << result << endl;

}



CLICK TO SEE THE OUTPUT.