// Tyler Rigsby, CSE 142
// Contains several math operations of our own creation
public class MyMath {
    public static void main(String[] args) {
        System.out.println(pow(2, -3));
        System.out.println(sum(15));
    }
    
    // Returns the result of the power; base to the exponent
    public static double pow(int base, int exponent) {
        double result = 1;
        for (int i = 1; i <= Math.abs(exponent); i++) {
            result *= base; // or, result = result * base
        }
        if (exponent < 0) {
            return 1.0 / result;
        } else {
            return result;
        }
    }
    
    // Returns the sum of all numbers from 1 to n; also
    // for numbers divisible by 7, prints the sum through that number
    // Sample output(15):
    // 
    // sum through 7 is 28
    // sum through 14 is 105
    //    (returns 120)
    public static int sum(int n) {
        int sum = 0;
        for (int i = 1; i <= n; i++) {
            sum += i;
            if (i % 7 == 0) {
                System.out.println("sum through " + i + " is " + sum);
            }
        }
        return sum;
    }
}