Question

need help with dice excercise

For example, if we were writing a calendar program of some sort, we might very well use an array with 366 spots to hold the days, not worrying about adding more days to the year. Exercise 23 (C level] For another example, suppose we want to simulate rolling two six-sided dice repeatedly, tallying how many times each total is rolled. We need a memory cell to count the number of times each of the possible values from 2 through 12 happens. So, we could declare variables like int c2, c3, c4, c5, c6, c7, c8, c9, c10, c11, c12; But, apart from how long it took to type that, then when we got the dice roll number, we would have to use a multi-case statement to decide which of these variables to increment. Instead, and to get a little hands-on experience with arrays, write a class Ex23 that just has a main method and uses an array to tally a bunch of dice rolls. Since the totals can only be between 2 and 12, inclusive, an array is a good choice (though you could certainly use ArrayList<Integer>, if the exercise wasn't demanding that you use an array). To make things a little easier, make an int array named count with 13 positions, indexed 0 through 12, and just not be worried about the two wasted cells count [0] and count[1]. Your program should ask the user for the desired number of rolls, and then simulate (use the Random class) rolling a pair of dice that many times, number of times, tallying how many times each total is seen, and then print a report of the number of times each result was seen.

Answer 1

Main.java E saved 1 import java.util.Scanner; 2 import java.util. Random; java version "1.8.0 31" Java (TM) SE Runtime Environment (build 1.8.0 31 Java HotSpot (TM) 64-Bit Server VM (build 25.31-5 > javac -classpath .:/run dir/junit-4.12.jar:/ru /run dir/json-simple-1.1.1.jar -d . Main.java > java -classpath ./run_dir/junit-4.12.jar:/run run dir/json-simple-1.1.1.jar Main How many rolls you want to try : 100 class Main { public static void main(String[] args) { int counts[] = new int[]{0,0,0,0,0,0,0,0,0,0,0,0,0}; Scanner sc = new Scanner(System.in); Random rand - new Random(); System.out.print("How many rolls you want to try : "); int rolls = sc.nextInt(); int dicei, dice2; Total 2 3 4 5 Count 9 4 8 12 7 8 12 for(int i=0;i<rolls; i++){ dice1 = rand.nextInt((6 - 1) + 1) + 1; dice2 = rand.nextInt((6 - 1) + 1) + 1; counts(dicel+dice2]+=1; System.out.printf("\n\nTotal\tCount"); for(int i=2;i<13;i++){ System.out.printf("\n%d\t%d", i, counts[i]); Activati Go to PC

code:

import java.util.Scanner;

import java.util.Random;

class Main {

public static void main(String[] args) {

int counts[] = new int[]{0,0,0,0,0,0,0,0,0,0,0,0,0};

Scanner sc = new Scanner(System.in);

Random rand = new Random();

System.out.print("How many rolls you want to try : ");

int rolls = sc.nextInt();

int dice1,dice2;

for(int i=0;i<rolls;i++){

dice1 = rand.nextInt((6 - 1) + 1) + 1;

dice2 = rand.nextInt((6 - 1) + 1) + 1;

counts[dice1+dice2]+=1;

}

System.out.printf("\n\nTotal\tCount");

for(int i=2;i<13;i++){

System.out.printf("\n%5d\t%d",i,counts[i]);

}

}

}