Hi i am having trouble with loops. I am confused on how to set up a way to get the
the lowest score
the highest score
the average of the scores
and If no scores were entered, display the message that “No test grade scores were entered”.
i also had to sent up a counter which i did, and i also had to validate if the score was from 0 to 100 which i did i just don't know what to do next
import java.util.Scanner;
public class loops {
public static void main(String[] args) {
Scanner keyboard = new Scanner(System.in);
int average = 0;
int count = 0;
int score;
System.out.print("Please enter first score:");
score = keyboard.nextInt();
while (score!=-1){
while ((score>=0)&&(score<=100)){
System.out.println("the score is between 0 to 100 ");
System.out.println("Please enter the next test score:");
score = keyboard.nextInt();
count = count + 1;
}
}
average = (score/count);
System.out.println("The average is " +average);
System.out.println("The number of test scores enter was:"+count);
}
}
See explanations in comments:
import java.util.Scanner;
public class Loops { //use java naming convention
public static void main(String[] args) {
Scanner keyboard = new Scanner(System.in);
int count = 0, score = 0, min = 0, max = 0, sum =0;
float average = 0;//the average might not be int
System.out.print("Please enter first score:");
score = keyboard.nextInt();
//add it to sum
sum = score;
//keep first number as min and max
min = score; max = score;
count++;//increment counter
//this is not needed, score of -1 will stop the next loop any way
//while (score!=-1){
while (true){
System.out.println("the score is between 0 to 100 ");
System.out.println("Please enter the next test score, or -1 to quit:");
score = keyboard.nextInt();
if((score < 0) ||(score > 100)) {
break;
}
count++;//increment counter
//you need to sum all entered numbers
sum += score;
//check if entered number is min
if(score < min) {
min = score ;
}
//check if entered number is max
if(score > max) {
max = score ;
}
}
if(count >0 ) {
average = ((float)sum/count);
System.out.println("The average is " +average );
System.out.println("The min is " +min);
System.out.println("The max is " +max);
System.out.println("The number of test scores enter was:"+count);
}else {
System.err.println("No numbers entered");
}
}
}
Don't hesitate to ask for clarifications as needed.
Related
I have a question which asks me to enter some exam score to find the highest and the lowest score overall. (Highlighted question.)
float sum = 0, score1, score2 = 0, score3 = 0;
do
{
System.out.println("Enter a score [negative score to quit]: ");
Scanner Score1 = new Scanner(System.in);
score1 = Score1.nextFloat();
if (score1>score2)
{
max = score1;
min = score2;
}
else if(score1<score2)
{
max = score2;
min = score1;
}
else{
score3 = score2;
}
}
}
while (score1>=0);
System.out.printf("Minimun Score = %.0f\n", min);
System.out.printf("Maximum Score = %.0f\n", max);
Enter a score [negative score to quit]:
99
Enter a score [negative score to quit]:
1
Enter a score [negative score to quit]:
6
Enter a score [negative score to quit]:
5
Enter a score [negative score to quit]:
-1
Minimum Score = 5
Maximum Score = 6
BUILD SUCCESSFUL (total time: 7 seconds)
The problem is it only compares the latest 2 score that I entered.
How do i fix this?
The do-while logic may not work in the above code. see the working code below..
float sum = 0, score = 0;
float min = 0, max = 0, ave = 0;
Scanner stdInput = new Scanner(System.in);
System.out.println("Enter the scores: ");
min = max = score = stdInput.nextFloat();
do {
System.out.println("Enter a score [negative score to quit]: ");
if (score > max) {
max = score;
}else if (score < min) {
min = score;
}
sum += score;
// Read the input here so that, the code does not process the negative input.
score = stdInput.nextFloat();
} while (score >= 0);
System.out.println(min);
System.out.println(max);
Logic in if-else ladder is incorrect.
You may find following useful:
class Test
{
public static void main (String[] args) throws java.lang.Exception
{
try(Scanner Score1 = new Scanner(System.in))
{
//Marks are in range of 0-100
float curNum, max = -1, min = 101, sum = 0, sumsq = 0;
boolean flg = true;
while(flg)
{
System.out.println("Enter a score [negative score to quit]: ");
curNum = Score1.nextFloat();
if(curNum<0) break;
if(max < curNum) max = curNum;
if(min > curNum) min = curNum;
sum += curNum;
sumsq += (curNum*curNum);
}
System.out.printf("Minimun Score = %.0f\n", min);
System.out.printf("Maximum Score = %.0f\n", max);
}
}
}
You can find it working here
This program is supposed to take user input of four grades, take these grades and calculate the lowest, highest and average of them. Then it needs to print out the four grades along with the lowest, highest, and average of them with proper labels. I cannot figure out how to print out the four grades with my code, and for some reason it prints out the lowest, highest and average after every iteration of the loop, or every user input.
Here is what I have so far:
public class Test2 {
double total = 0.0;
double max = 0.0;
double min = Double.MAX_VALUE;
public void Test2 (double[] grades){
//Loop through all of the grades.
for(int i = 0; i < 4; i++){
double grade = grades[i];
//Add the grade to the total
total += grade;
//If this is the highest grade we've encountered, set as the max.
if(max < grade){
max = grade;
}
//If this is the lowest grade we've encountered, set as min.
if(min > grade){
min = grade;
}
}
System.out.println("Average is: " + (total / 4));
System.out.println("Max is: " + max);
System.out.println("Min is: " + min); }
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
double[] grades = new double[4];
System.out.println("Please enter number");
for (int i = 0; i < grades.length; i++) {
grades[i] = input.nextDouble();
Test2 g = new Test2();
g.Test2(grades);
} } }
Can anyone help me with this? I need it to print out the four grades (user input), along withe the lowest, highest and average grade from the four grades, but ONLY ONCE, not after every iteration of the loop. Sorry if my code looks bad.
You have to call the method Test2(double grade) only once in the main method as there is a for loop inside Test2 method. I.e call Test2 method in main outside for loop.
Your answer should be the below class.
import java.util.Scanner;
public class Test2 {
double total = 0.0;
double max = 0.0;
double min = Double.MAX_VALUE;
public void doOperations(double[] grades) {
for (int i = 0; i < 4; i++) {
double grade = grades[i];
//Add the grade to the total
total += grade;
//If this is the highest grade we've encountered, set as the max.
if (max < grade) {
max = grade;
}
//If this is the lowest grade we've encountered, set as min.
if (min > grade) {
min = grade;
}
}
System.out.println("Average is: " + (total / 4));
System.out.println("Max is: " + max);
System.out.println("Min is: " + min);
}
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
double[] grades = new double[4];
System.out.println("Please enter number");
for (int i = 0; i < grades.length; i++) {
grades[i] = input.nextDouble();
}
Test2 test2 = new Test2();
test2.doOperations(grades);
}
}
The first part of the exercise was to calculate the test score average. The next problem asked me to build off this problem and calculate the minimum and maximum. Can anyone help me? This is my code so far.
import java.util.Scanner;
import java.io.*;
import java.text.DecimalFormat;
public class hw
{
public static void main ( String[] args )
{
int maxGrade;
int minGrade;
int count=0;
int total=0;
final int SENTINEL = -1;
int score;
Scanner scan = new Scanner( System.in);
System.out.println( "To calculate the class average, enter each test
score.");
System.out.println( "When you are finished, enter a -1.");
System.out.print( "Enter the first test score > ");
score = scan.nextInt();
while (score != SENTINEL )
{
total += score;
count ++;
System.out.print("Enter the next test score > ");
score = scan.nextInt();
}
if (count != 0)
{
DecimalFormat oneDecimalPlace = new DecimalFormat("0.0");
System.out.println( "\nThe class average is "
+ oneDecimalPlace.format( (double) (total) / count ));
}
else
System.out.println("\nNo grades were entered");
}
}
in your while loop, you can compare the current score to the maximum and the minimum.
while (score != SENTINEL )
{
total += score;
count ++;
if(score > maxGrade)
maxGrade = score;
if(score < minGrade)
minGrade = score;
System.out.print("Enter the next test score > ");
score = scan.nextInt();
}
You also need to set the max and min (when declaring them) to their "opposite" value:
int maxGrade = Integer.MIN_VALUE;
int minGrade = Integer.MAX_VALUE;
So here is my code:
package e7;
import java.util.Scanner;
public class Q1 {
public static void main(String[] args)
{
double[] scores = new double[10];
double sum = 0.0D;
int count = 0;
Scanner sc = new Scanner(System.in);
do {
System.out.print("Enter a new score (-1 to end): ");
scores[count] = sc.nextDouble();
if (scores[count] >= 0.0D)
sum += scores[count];
}
while (scores[(count++)] >= 0.0D);
System.out.println("The total number of scores is: " + count );
double average = sum / (count - 1);
int numOfAbove = 0;
int numOfBelow = 0;
for (int i = 0; i < count - 1; i++) {
if (scores[i] >= average)
numOfAbove++;
else
numOfBelow++;
}
System.out.printf("Average is " + "%.2f\n",average);
System.out.println("Number of scores above or equal to the average " + numOfAbove);
System.out.println("Number of scores below the average " + numOfBelow);
}
}
How do make it display the correct number of scores calculated? If I input 2 numbers and then do the -1 one to end it keeps saying 3 scores. Should only be two. How do I fix this? Thanks
System.out.println("The total number of scores is: " + count );
You probably want:
System.out.println("The total number of scores is: " + (count - 1));
You could also change your loop from a do while to a while loop as follows,
while (true) {
System.out.print("Enter a new score (-1 to end): ");
double tempDouble = sc.nextDouble();
if (tempDouble >= 0.0D)
scores[count] = tempDouble;
sum += scores[count];
count++;
else
break;
}
That way as if your double input isn't correct it would break out of the while loop when the user entered -1. You might have to tweak it a bit for your use case.
I have a java program that takes the scores of 4 players and computes each player's average score when -1 is inputted. At the end of the program I need to display the highest average score out of the 4 averages, however I cannot figure out how to do this, can you guys set me in the right direction? The program looks like this when it is run: (I have also attached my code) I cannot use anything but loops.
Player 1
Enter your score: 100
Enter your score: 90
Enter your score: 80
Enter your score: 70
Enter your score: -1 (when -1 is inputted, the average score is calculated)
Average Score = 85.00
Player 2
Enter your score: 90
Enter your score: 90
etc.
etc.
import java.util.Scanner;
public class BowlingScores
{
public static void main(String[]args)
{
double score = 0;
double totalScore = 0;
double count = 0;
Scanner input = new Scanner(System.in);
for (int player = 1; player <= 4; player++){
System.out.printf("\nPlayer %d\n", player);
do{
System.out.println("Enter Your Score: ");
totalScore = totalScore + score;
score = input.nextDouble();
count++;
} while (score != -1);
if (score == -1){
count--;
System.out.printf("Average Score = %.2f\n",totalScore/count);
count = 0;
score = 0;
totalScore = 0;
}
}
}
}
Just keep track of the highest average in another variable. Then in your score == -1 condition check to see if the current average is higher than the highest average, and if so make current the new highest. Then after your for loop you could print out the highest average.
You can add a copy of the highest at the top of your code like this double highest = 0 then in your for loop have a way to replace it if the current average is higher.
if(score > highest){
highest=score;
}
Then at the -1 you can either reset it to 0 or keep it going.
public static void main(String[] args) {
final List<Double> allAverages = new ArrayList<>();
double score = 0;
double totalScore = 0;
double avg = 0;
int count = -1;
Scanner input = new Scanner(System.in);
for (int player = 1; player <= 4; player++) {
System.out.printf("\nPlayer %d\n", player);
do {
System.out.println("Enter Your Score: ");
totalScore = totalScore + score;
score = input.nextDouble();
count++;
} while (score != -1);
avg = totalScore / count;
System.out.printf("Average Score = %.2f\n", avg);
allAverages.add(totalScore / count);
score = 0;
totalScore = 0;
count = -1;
}
System.out.println("The highest is : " + Collections.max(allAverages));
}
Here a list of the modifications I did to your code to get it working :
The variable count now start at -1, so there is no need to do count-- when we exit the loop.
I've added a List that keep a track of all the averages.
I've removed the validation if(count == -1) after the loop as the only way to exit the loop is to have count == -1 so we already know it is the actual value.
To retrieve the maximum of all averages, I use Collections.max(allAverages).
Take average of all 4 players and store into one array. Then check for the largest number in array.
double[] highest = new double[4];
for(int i=0; i<4; i++){
highest[i] = totalScore/count;
}
if(highest[0]>highest[1] && highest[0]>highest[2] && highest[0]>highest[3])
System.out.println("highest" + highest[0]);
else if(highest[1]>highest[0] && highest[1]>highest[2] && highest[0]>highest[3])
System.out.println("highest" + highest[1]);
else if(highest[2]>highest[0] && highest[2]>highest[1] && highest[0]>highest[3])
System.out.println("highest" + highest[2]);
else System.out.println("highest" + highest[3]);
public static void main(String[]args) {
double bestScore = 0;
int bestPlayer = 1;
Scanner input = new Scanner(System.in);
for (int player = 1; player <= 4; player++){
System.out.printf("\nPlayer %d\n", player);
int count = 0; // does not need to be double
double totalScore = 0;
do {
System.out.println("Enter Your Score: ");
double score = input.nextDouble();
if (score != -1) {
totalScore += score;
count++;
}
} while (score != -1);
double averageScore = totalScore / count;
if (averageScore > bestScore) {
bestScore = averageScore;
bestPlayer = player;
}
System.out.printf("Average Score = %.2f\n", averageScore);
}
System.out.printf("Best Average Score = %.2f, best player = %d\n", bestScore, bestPlayer);
}
Just keep a variable to record the top average score every time as in topAverage in my example below. The code is same as your's except I changed the variable names for my readability.
public static void main(String[] args) throws NumberFormatException,
IOException {
double currentScore = 0;
double totalScore = 0;
int numScores = 0;
double averageScore = 0;
double topAverage = 0;
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
for (int i = 0; i < 4; i++) {
do {
System.out.println("Enter Score");
currentScore = Double.parseDouble(br.readLine());
totalScore = totalScore + currentScore;
numScores += 1;
} while (currentScore != -1);
numScores-=1;
totalScore+=1;
averageScore = totalScore / numScores;
System.out.println("Average Score is " + averageScore);
if (topAverage < averageScore) {
topAverage = averageScore;
}
currentScore = 0;
totalScore = 0;
numScores = 0;
}
System.out.println("Top Average is " + topAverage);
}
Edit
#Andrei Nikolaenko posted the same answer before me, so consider that answer, I am adding this edit because I want to mention that my browser did not refresh on time to show me that the answer has already been posted.