increment calculator

#include <iostream>
#include <stdlib.h>

using namespace std;

int main()
{
    /*Let user input number then amount of percentage
    he/she want to increase the number with.*/

    double number;
    double percentage_input;

    cout << "Input number: ";
    cin >> number; cout << endl;

    cout << "Input percentage";
    cin >> percentage_input; cout << "%" << endl;

    double percentage = percentage_input / 100;

    double increase_result = (number * percentage) + number;

    cout << "Increase of " << number << " with "
    << percentage_input << " is equal to " <<
    increase_result;

    return 0;
}