Utopian Tree - HackerRank Solutions

The Utopian Tree goes through 2 cycles of growth every year. Each spring, it doubles in height. Each summer, its height increases by 1 meter.

A Utopian Tree sapling with a height of 1 meter is planted at the onset of spring. How tall will the tree be after n growth cycles?

For example, if the number of growth cycles is n=5, the calculations are as follows:

Period  Height

0          1

1          2

2          3

3          6

4          7

5          14

Function Description

Complete the utopianTree function in the editor below.

utopianTree has the following parameter(s):

• int n: the number of growth cycles to simulate

Returns

• int: the height of the tree after the given number of cycles

Input Format

The first line contains an integer, t, the number of test cases.

 t subsequent lines each contain an integer, n, the number of cycles for that test case.

Constraints

1≤t≤10

0≤n≤60

Sample Input

3

0

1

4

Sample Output

1

2

7

Explanation

There are 3 test cases.

In the first case (n=0), the initial height (H=1) of the tree remains unchanged.

In the second case (n=1), the tree doubles in height and is 2 meters tall after the spring cycle.

In the third case (n=4), the tree doubles its height in spring (n=1, H=2), then grows a meter in summer (n=2, H=3), then doubles after the next spring (n=3, H=6 ), and grows another meter after summer (n=4, H=7). Thus, at the end of 4 cycles, its height is 7 meters.

---

Utopian Tree - HackerRank Solutions

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;
public class Solution {
    // Complete the utopianTree function below.
    static int utopianTree(int n) {
        int h = 1;
        for (int i = 1; i <= n; i++) {
            if (i % 2 != 0)
                h = h * 2;
            else
                h = h + 1;
        }
        return (h);
    }
    private static final Scanner scanner = new Scanner(System.in);
    public static void main(String[] args) throws IOException {
        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));
        int t = scanner.nextInt();
        scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");
        for (int tItr = 0; tItr < t; tItr++) {
            int n = scanner.nextInt();
            scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");
            int result = utopianTree(n);
            bufferedWriter.write(String.valueOf(result));
            bufferedWriter.newLine();
        }
        bufferedWriter.close();
        scanner.close();
    }
}