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@anirudhpillai
Last active January 28, 2016 13:35
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Put the input in a text file. Then in the variable path (in main method), add the path to the text file.
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.stream.Stream;
public class Robot {
private static int gridX;
private static int gridY;
private static HashMap<String, Integer> scents = new HashMap<>();
/*
the directions currently correspond to [N, E, S, W]
they are in clockwise direction
if NE has to be added then {1,1} can be added as second element
to give corresponding directions as [N, NE, E, S, W]
{1, 1} because if the robot moves NE then it will increase both its x and y coordinate
*/
private static int[][] directions = {{0, 1}, {1, 0}, {0, -1}, {-1, 0}};
private int x;
private int y;
private boolean isFallen = false;
private int directionIndex = 0;
public Robot(int x, int y, char orient){
this.x = x;
this.y = y;
switch(orient){
case 'N': this.directionIndex = 0;
break;
case 'E': this.directionIndex = 1;
break;
case 'S': this.directionIndex = 2;
break;
case 'W': this.directionIndex = 3;
break;
}
}
public static void setGridSize(int gx, int gy){
gridX = gx;
gridY = gy;
}
private char currentOrientation(){
switch (this.directionIndex){
case 0: return 'N';
case 1: return 'E';
case 2: return 'S';
default: return 'W';
}
}
public void changeOrientation(char a) {
switch (a) {
case 'R':
directionIndex++;
directionIndex %= directions.length;
break;
case 'L':
if (directionIndex == 0)
directionIndex = directions.length - 1;
else
directionIndex--;
break;
}
}
public boolean forward() {
String add = "" + this.x + this.y + directions[directionIndex][0] + directions[directionIndex][1];
if (scents.containsKey(add)) {
return true;
}
int newX = this.x + directions[directionIndex][0];
int newY = this.y + directions[directionIndex][1];
if (newX > gridX || newY > gridY) {
scents.put(add, 1);
this.isFallen = true;
return false;
}
this.x = newX;
this.y = newY;
return true;
}
public boolean move(char a) {
switch (a) {
case 'F':
return this.forward();
case 'R':
this.changeOrientation(a);
return true;
case 'L':
this.changeOrientation(a);
return true;
}
return false;
}
public String toString(){
return this.x + " " + this.y + " " + this.currentOrientation() + " " + (this.isFallen ? "LOST" : "");
}
public static String launch(Robot rob, String input){
for(int i = 0; i<input.length(); i++){
if(!rob.move(input.charAt(i))){
return rob.toString();
}
}
return rob.toString();
}
public static void main (String args[]){
String path = "";
ArrayList<String> input = new ArrayList<>();
try (Stream<String> stream = Files.lines(Paths.get(path))){
stream.filter(p -> !p.equals("")).forEach(input::add);
} catch (IOException e){
e.printStackTrace();
}
ArrayList<String> temp = answer(input);
for(String i: temp){
System.out.println(i);
}
}
public static ArrayList<String> answer(ArrayList<String> input){
String[] one = input.get(0).split(" ");
Robot.setGridSize(Integer.parseInt(one[0]), Integer.parseInt(one[1]));
ArrayList<String> ans = new ArrayList<>();
for(int i = 1; i<input.size()-1; i+=2){
String[] init = input.get(i).split(" ");
Robot rob = new Robot(Integer.parseInt(init[0]), Integer.parseInt(init[1]), init[2].charAt(0));
String a = Robot.launch(rob, input.get(i+1));
ans.add(a);
}
return ans;
}
}
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