Question

"The Drunkard’s Walk. A drunkard in a grid of streets randomly picks one of four directions and stumbles to the next intersection, then again randomly picks one of four directions, and so on. You might think that on average the drunkard doesn’t move very far because the choices cancel each other out, but that is actually not the case."

for java 1.7

Answer 1

Solution:

import java.util.*;
// declare class
public class drunkardWalk{
        //declare the main method
        public static void main(String[] args) {
                 
                // welcome the user
                System.out.println("If a drunk person at location (x,y) randomly travels i various directions in a grid city. What happens after 100 random choices.");

                Random randomGenerator = new Random();
                int x = 0;
                int y = 0;
                double distance = 0;
                for (int decisionCounter = 0; decisionCounter < 100; decisionCounter ++){
                        int direction = randomGenerator.nextInt(4) + 1 ;

                         switch (direction) {
                         case 1: x = x + 1; //going east one block
                                break;
                         case 2: x = x + -1;//going west one block
                                break;
                                
                         case 3: y = y + 1;//going north one block
                                break;
                                
                         case 4: y = y - 1;//going south one block\
                                break;
                         }//switch END
                        
                }//loop END
                // d= sqrt of [(x - 0)^2 + (y - 0)^2]
                distance = Math.sqrt(((x * x) + (y * y)));
                
                
                
                System.out.printf("If the city blockes are one mile by one mile then the drunk person has traveled %4.2f", distance);
                System.out.println(" miles away from his original location by walking 100 miles. ");
                  
  
        }//main END
}//class END

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