Question

The input will be a String with multiple not-always-lowercase directions separated by underscores. The last character of the input is always an underscore. You must output the final (x, y) coordinates of a robot, starting at (0, 0), after it has followed all of the directions. Print the result in the format “Result: (x, y)”

USE THE SKELETON PROGRAM PROVIDED.

Example #1:

INPUT: up_down_left_down_down_

Result: (-1, -2)

up --move→ y + 1 = 1

down --move→ y - 1 = 0

left --move→ x - 1 = -1

down --move→ y - 1 = -1

down --move→ y - 1 = -2

x = -1, y = -2 at the end

Example #2:

INPUT: up_dOwn_riGHt_LefT_

Result: (0, 0)

/*

* Notice the globally-scoped x and y variables at the top of the class */

import java.util.Scanner;

public class Robot {

public static int x = 0;

public static int y = 0;

public static void main(String[] args) {

Scanner console = new Scanner(System.in);

String directions = console.nextLine();

readDirections(directions);

}

// Isolates each direction as a String in a loop

public static void readDirections(String dirs) {

}

// Moves the robot by editing the x and y variables

public static void move(String dir) {

}

}

Answer 1

Program: In this program, given an input string of directions, we calculate the final (x, y) coordinates of a robot, starting at (0, 0), after it has followed all of the directions. Inside the function readDirections(String dirs) we process the string- convert it to lowercase, remove the ending underscore, then split it into an array based on the regex underscore and then to update the coordinates, traverse each direction in a loop and call move(String dirs) function. Indside the move() function, we update x,y based on direction value.

Code:

import java.util.Scanner;

public class Robot {

    public static int x = 0;

    public static int y = 0;

    public static void main(String[] args) {

        Scanner console = new Scanner(System.in);
        String directions = console.nextLine();

        readDirections(directions);

        System.out.println("(" + x + ", " + y + ")");
    }

// Isolates each direction as a String in a loop

    public static void readDirections(String dirs) {

        // Convert string to lowercase
        dirs = dirs.toLowerCase();

        // Remove ending underscore
        dirs = dirs.substring(0, dirs.length() - 1);

        // Split array based on underscore
        // Example: dirs = "up_down_left_down_down" -> dirArray = {"up","down","left","down","down"}
        String[] dirArray = dirs.split("_");

        // Traverse each directions and call move() function
        for (int i = 0; i < dirArray.length; i++) {
            move(dirArray[i]);
        }
    }

// Moves the robot by editing the x and y variables

    public static void move(String dir) {

        // Check if direction is up, down, left or right
        if (dir.equals("up")) {
            y++;
        } else if (dir.equals("down")) {
            y--;
        } else if (dir.equals("left")) {
            x--;
        } else {
            x++;
        }
    }
}

Output 1:

Output 2: