Sum of Squares and Cubes

/*
 * Problem : Find 1^2 + 2^2 + ... + n^2 and 1^3 + 2^3 + ... + n^3.
 * Input   : One integer n (n >= 0).
 * Output  : Two lines: Sum of squares and Sum of cubes.
 * Approach: Use the formulas n(n+1)(2n+1)/6 and (n(n+1)/2)^2.
 * Time    : O(1)
 * Space   : O(1)
 * Java    : 8 or newer.
 */
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        long n = new Scanner(System.in).nextLong();

        // Step 1: Sum of squares is n(n+1)(2n+1)/6. Example: n = 3 gives 14.
        long squares = n * (n + 1) * (2 * n + 1) / 6;

        // Step 2: Sum of cubes is the square of 1 + 2 + ... + n. Example: n = 3 gives 36.
        long triangular = n * (n + 1) / 2;
        long cubes = triangular * triangular;

        // Step 3: Print both results.
        System.out.println("Sum of squares: " + squares);
        System.out.println("Sum of cubes: " + cubes);
    }
}