Im having some trouble on getting my methods to work, I believe I am doing something wrong in the main method to call the others. I am not sure if I need an if, while, or for statement. Can anyone help, I really appreciate it. Here is my program...
public static void main(String[] args) throws IOException {
Scanner kb = new Scanner(System.in);
final int MAX = 100;
int [] myarray = new int [MAX];
int fillsize, total = 0, num;
int smallest = 0, largest = 0;
fillsize = fillarray (myarray, MAX);
printarray (myarray, fillsize);
num = kb.nextInt();
int small = num;
int large = num;
total = Average(total, num);
if(smallest (num, smallest))
{
small = num;
}
if(largest(num, largest))
{
large = num;
}
System.out.println("The smallest value is: " + smallest);
System.out.println("The largest value is: " + largest);
System.out.println("The average is: " + total);
prw.close();
}
public static int fillarray (int[] num, int MYMAX){
Random gen = new Random();
int retval = 0;
int randomnum;
for(int count = 0; count <= 30; count++){
randomnum = gen.nextInt(150);
num [count] = randomnum;
System.out.println(randomnum);
retval++;
}
System.out.println("The return value is: " + retval);
return (retval);
}
public static void printarray (int[] num, int fillsize){
for (int counts = 0; counts < fillsize; counts++){
System.out.println("For the position ["+counts+"] the value is " + num[counts]);
}
return;
}
public static boolean smallest (int num1, int num2){
boolean returnValue;
if (num2 < num1){
returnValue = true;
}
else {
returnValue = false;
}
return (returnValue);
}
public static boolean largest (int number1, int number2){
boolean returnVal;
if (number1 > number2){
returnVal = true;
}
else{
returnVal = false;
}
return (returnVal);
}
public static int Average (int avg, int sum){
int retVal;
retVal = avg + sum;
return(retVal);
}
What am I doing wrong?
I suspect the problem is you set smallest and largest both to num which makes your if redundant.
Try setting them both to 0.
Also you have variables and methods with the same name which isn't recommended. (confusing).
Related
Problem: Statistics are often calculated with varying amounts of input data. Write a program that takes any number of non-negative integers as input, and outputs the average and max. A negative integer ends the input and is not included in the statistics.
Ex: When the input is:
15 20 0 5 -1
the output is:
10 20
You can assume that at least one non-negative integer is input.
import java.util.Scanner;
public class LabProgram {
public static void main(String[] args) {
Scanner scnr = new Scanner (System.in);
int num = 0;
int count = 0;
int max = 0;
int total = 0;
int avg = 0;
do {
total += num;
num = scnr.nextInt();
count = ++count;
if (num >= max) {
max = num;
}
} while (num >= 0);
avg = total/(count-1);
System.out.println(avg + " " + max);
}
}
I had a lot of trouble with this problem. Is there any way I could have done this without having to do count -1 while computing the average?
Also, is this this the most efficient way I could have done it?
How about this? If you have questions from the implementation, please ask.
public static void main(String[] args) throws IOException {
Scanner scnr = new Scanner(System.in);
int count = 0, max = 0, total = 0;
int num = scnr.nextInt();
while (num >= 0) {
count++;
total += num;
max = Math.max(max, num);
num = scnr.nextInt();
}
int avg = count == 0 ? 0 : total/count;
System.out.println(avg + " " + max);
}
If you use while loop instead of do-while loop, you don't have to count the negative number input anymore. And no, it's not the most efficient way, but it's a good start!
import java.util.Scanner;
public class LabProgram {
public static void main(String[] args) {
Scanner scnr = new Scanner (System.in);
int userNum;
int maxNum = 0;
int totalSum = 0;
int averageNum;
int count = 0;
userNum = scnr.nextInt();
while (userNum >= 0) {
if (userNum > maxNum) {
maxNum = userNum;
}
totalSum += userNum;
++count;
userNum = scnr.nextInt();
}
averageNum = totalSum / count;
System.out.println("" + averageNum + " " + maxNum);
}
}
int Num;
int max = 0;
int total = 0;
int average;
int count = 0;
Num = scnr.nextInt();
while (Num >= 0) {
if (Num > max) {
max = Num;
}
total += Num;
++count;
Num = scnr.nextInt();
}
average = total / count;
System.out.println("" + average + " " + max);
}
}
I'm having issues getting all prime numbers between a given integer A and integer B.
The issue is that the output goes well beyond whatever I defined for B. I thought that the
if (isPrime){
count++;
would fix this but the output still goes well beyond the intended number of integer B.
For example if int valueA = 1 and int valueB = 100, it'll get prime numbers from around 1 to 500 before stopping, instead of just ending the check at 100.
Thank you for any assistance.
import java.util.*;
public class PrimeNumbersTest {
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner input = new Scanner(System.in);
// Ask user to input an integer value for A and B
System.out.print("Enter the value of A (must be an integer): ");
int valueA = input.nextInt();
System.out.print("Enter the value of B (must be an integer): ");
int valueB = input.nextInt();
System.out.println("The prime numbers between " + valueA + " and " + valueB + " are:");
final int LINE = 10;
int count = valueA;
int number = 2;
while (count < valueB) {
// Assume the number is prime
boolean isPrime = true;
// Test if number is prime
for (int divisor = 2; divisor <= number / 2; divisor++) {
if (number % divisor == 0) { // If true number is not prime
isPrime = false; // Set isPrime to false
break; // Exit the for loop
}
}
if (isPrime) {
count++;
if (count % LINE == 0) {
System.out.println(number);
}
else
System.out.print(number + " ");
}
number++;
}
}
}
When you want to work on a range of number, use a for loop instead of while loop to reduce confusion. You obviously want
for(int number = valueA; number <= valueB; number++){/*check if number is prime*/}
Example:
public static void main(String []args){
int valueA = 1;
int valueB = 100;
int count = 0;
for(int number = valueA; number <= valueB; number++)
{
if(isPrime(number))
{
count++;
System.out.println(number);
}
}
System.out.println("count = " + count);
}
public static boolean isPrime(int n)
{
for(int i = 2; i*i <= n; i++)
{
if(n % i == 0)
{
return false;
}
}
return n > 1;
}
For your requirement of checking isPrime inline:
public static void main(String []args){
int valueA = 1;
int valueB = 100;
int count = 0;
for(int number = valueA; number <= valueB; number++)
{
boolean isPrime = number > 1;
for(int i = 2; i*i <= number; i++)
{
if(number % i == 0)
{
isPrime = false;
break;
}
}
if(isPrime)
{
count++;
System.out.println(number);
}
}
System.out.println("count = " + count);
}
I want to create program read more than 10 numbers from the user and find the maximum number and minimum number then print all the numbers from the user.
This is my program, but I don't know how can I find the maximum number and minimum number:
import java.io.*;
public class ass3 {
public static void main (String [] args) throws IOException
{
int times , num1 ;
int max , min;
System.out.print("How many numbers you want to enter?\n*moer than five number");
times=IOClass.getInt();
if (times>5) {
for(int i = 0;i<times;i++){
System.out.println("please type the "+i+ "number");
num1=IOClass.getInt();
}
}
}
}
If you initialize the min and max like this:
int min = Integer.MAX_VALUE;
int max = Integer.MIN_VALUE;
You can check whether the new number is smaller than min or bigger than max, and change them if needed:
int num = ...;
if (num < min) {
min = num;
}
if (num > max) {
max = num;
}
This is my solution, hope it helps:
import java.util.Scanner;
public class Test
{
public static void main(String[] args)
{
Scanner in = new Scanner(System.in);
System.out.print("How many numbers you want to enter?\nThe number must be grater than 5");
int times = in.nextInt();
if (times > 5)
{
int[] numbers = new int[times];
int min = Integer.MAX_VALUE;
int max = Integer.MIN_VALUE;
for(int i = 0; i < times; i++)
{
System.out.println("Please type the " + i + " number:");
int number = in.nextInt();
numbers[i] = number;
if(number < min)
{
min = number;
}
if(number > max)
{
max = number;
}
}
System.out.println("Max: " + max);
System.out.println("Min: " + min);
}
in.close();
}
}
For some reason the average is being populated wrong when I pass the array to the method I get a really low percent. It almost seems like since the Array shotsMade is only recording integers for made shots and not misses it is not calculating off the right base.
import java.util.*;
public class Test {
public static void main(String[] args) {
int myGameCounter = 1;
int shotCount = 0;
int shotCount1 = 0;
int [] shotsMade = new int [5];
int sum = 0;
System.out.print("Enter Player's Free Throw Percentage: ");
Scanner input = new Scanner(System.in);
int percent = input.nextInt();
//Game #1
System.out.println("Game " + myGameCounter + ":");
Random r = new Random();
myGameCounter++;
shotCount = 0;
for (int i = 0; i < 10; ++i){
boolean in = tryFreeThrow(percent);
if (in) {
shotCount++;
System.out.print("In" + " ");
}
else {
System.out.print("Out" + " ");
}
}
System.out.println("");
System.out.println("Free throws made: " + shotCount + " out of 10");
shotsMade[0]= shotCount;
//Game #2
System.out.println("");
System.out.println("Game" + myGameCounter + ":");
myGameCounter++;
shotCount1 = 0;
for (int i = 0; i < 10; ++i){
boolean in = tryFreeThrow(percent);
if (in) {
shotCount1++;
System.out.print("In" + " ");
}
else {
System.out.print("Out" + " ");
}
}
System.out.println("");
System.out.println("Free throws made: " + shotCount1 + " out of 10");
shotsMade[1]= shotCount1;
System.out.println("");
System.out.println("Summary:");
System.out.println("Best game: " + max(shotsMade));
System.out.println("Total Free Throws Made: " + sum(shotsMade) + " " + "out of 20");
System.out.println("Average Free Throw Percentage: " + average(shotsMade) +"%");
}//main
public static boolean tryFreeThrow(int percent) {
Random r = new Random();
int number = r.nextInt(100);
if (number > percent){
return false;
}
return true;
}
public static float average(int nums[]) {
int total = 0;
for (int i=0; i<nums.length; i++) {
total = total + nums[i];
}
float f = (total / nums.length);
return (float)total /(float)nums.length;
}
public static int sum(int nums[]) {
int sum = 0;
for (int i=0; i<nums.length; ++i) {
sum += nums[i];
}
return (int)sum;
}
public static int max(int nums[]) {
int max=nums[0];
for (int i=1; i<nums.length; i++) {
if (nums[i] > max)
max = nums[i];
}
return max;
}
}//class
You are calculating the avarage of 5 numbers but you only set 2. So if all shots hit your array will look like this: 10, 10, 0, 0, 0 and the avarage will be 4.
Old issue, you are using integer arithmetic total / nums.length with returns you an int value. You later assign it to a float, but the value already has been truncated.
Just change one of the values to float before the division, v.g. ((float) total) / num
Among others, your expression
float f = (total / nums.length);
will yield an inaccurate result.
Both total and nums.length are integers, and any operation between integers always results in an integer.
Example: if total=10 and nums.length=3, you'd expect the result to be 3.333... but actually the result is just 3. Only after that do you cast it to a float, resulting in 3.0.
To get the required result, you need to cast both integers to floats before dividing:
float f = (float) total / (float) nums.length;
I am not sure if what I am asking is right, but originally i had this run 5 times in the main. however i felt that a do/while loop could do the same thing. But now I cannot get the array shotsMade to change from shotsMade[0] to shotsMade[1] etc, and the shotCount to store to it. It will only store the last run of the while loop. What can I change to make those 2 items increment so the methods still calculate the data correctly
import java.util.*;
public class Final {
public static void main(String[] args) {
int myGameCounter = 1;
int [] shotsMade = new int [5];
System.out.print("Enter Player's Free Throw Percentage: ");
Scanner input = new Scanner(System.in);
int percent = input.nextInt();
//Game
do{
System.out.println("Game " + myGameCounter + ":");
Random r = new Random();
myGameCounter++;
int shotCount = 0;
for (int i = 0; i < 10; ++i){
boolean in = tryFreeThrow(percent);
if (in) {
shotCount++;
System.out.print("In" + " ");
}
else {
System.out.print("Out" + " ");
}
}
System.out.println("");
System.out.println("Free throws made: " + shotCount + " out of 10");
System.out.println("");
shotsMade[0]= shotCount;// I need shotsMade[0] to change each loop, shotsMade[1], shotsMade[2], shotsMade[3], shotsMade[4]
} while (myGameCounter <=5);
System.out.println("");
System.out.println("Summary:");
System.out.println("Best game free throws made: " + max(shotsMade));
System.out.println("Worst game free throws made: " + min(shotsMade));
System.out.println("Total Free Throws Made: " + sum(shotsMade) + " " + "out of 50");
System.out.println("Average Free Throw Percentage: " + average(shotsMade) +"%");
}
public static boolean tryFreeThrow(int percent) {
Random r = new Random();
int number = r.nextInt(100);
if (number > percent){
return false;
}
return true;
}
public static int average (int nums[]) {
int total = 0;
for (int i=0; i<nums.length; i++) {
total = total + nums[i];
}
int average = total*10 / nums.length;
return average;
}
public static int sum(int nums[]) {
int sum = 0;
for (int i=0; i<nums.length; ++i) {
sum += nums[i];
}
return (int)sum;
}
public static int max(int nums[]) {
int max = nums[0];
for (int i=1; i<nums.length; i++) {
if (nums[i] > max)
max = nums[i];
}
return max;
}
public static int min(int nums[]) {
int min = nums[0];
for (int i=1; i<nums.length; i++) {
if (nums[i] < min)
min = nums[i];
}
return min;
}
}
Two things:
Move myGameCounter++; just below where you set shotsMade[]
Otherwise, you are increasing the game counter to 2 before the first game finished.
It should look like:
shotsMade[myGameCounter-1]= shotCount;
myGameCounter++;
} while (myGameCounter <=5);
Set shotsMade[myGameCounter-1]= shotCount; instead of shotsMade[0]= shotCount;
Otherwise, you are overwriting the value of shotsMade[0]
This way, you are re-using a counter as index for the array. Since myGameCounter will increase by one after each game (after you changed point 1) and it starts from 1, using myGameCounter - 1 will yield the correct index for your array shotsMade.