Java - Vertical Histogram troubleshoot: broken max value?

So after much trial and error I converted my horizontal histogram to a vertical one, at least partially.

It seems that instead of reading the highest number of times used, it simply reads the value of the highest-used number:

How many input values [max:30]?
5
Enter 5 numbers.
2
1
2
0
2
Number Occurrence
0 1
1 1
2 3
========= Vertical Bar ========
2	 |     * 
1	 | * * * 
===============================
| No | 0 1 2 3 4 5 6 7 8 9
===============================

leaves out the max height of 3 and removes an asterisk

How many input values [max:30]?
1
Enter 1 numbers.
5
Number Occurrence
5 1
========= Vertical Bar ========
5	 |   
===============================
| No | 0 1 2 3 4 5 6 7 8 9
===============================

does not print

5
Enter 5 numbers.
3
3
3
3
3
Number Occurrence
3 5
========= Vertical Bar ========
3	 | * 
===============================
| No | 0 1 2 3 4 5 6 7 8 9
===============================

prints the wrong max, the wrong number of asterisks, and in the wrong spot

How many input values [max:30]?
10
Enter 10 numbers.
5
4
3
2
1
1
2
3
4
5
Number Occurrence
1 2
2 2
3 2
4 2
5 2
========= Vertical Bar ========
5	 |           
4	 |           
3	 |           
2	 | * * * * * 
1	 | * * * * * 
===============================
| No | 0 1 2 3 4 5 6 7 8 9
===============================

adds whitespace for 5-3

10
Enter 10 numbers.
2
2
3
3
3
4
4
4
4
1
Number Occurrence
1 1
2 2
3 3
4 4
========= Vertical Bar ========
4	 |       * 
3	 |     * * 
2	 |   * * * 
1	 | * * * * 
===============================
| No | 0 1 2 3 4 5 6 7 8 9
===============================

works as intended although not by design

public class Histogram
{
public static void main(String[] args) {
//variables
Scanner keyboard = new Scanner(System.in);
int numInputs = 1, temp, maximum = 0;
int[] numbers = new int[31];
int[] count = new int[31];
boolean success = false;
//start of program
System.out.println("How many input values [max:30]?");
//while no valid input
while (!success) {
try {
numInputs = keyboard.nextInt(); //get a number
numInputChecker(numInputs);     //is it valid?
success = true;                 //ok
} catch (Exception e)                 //else get a new number
{
keyboard.nextLine();
System.out.println("Whole numbers 1 through 30 only, please.");
}
}
//reset the loop checker
success = false;
//read numbers to fill that array
System.out.println("Enter " + numInputs + " numbers.");
for (int i = 0; i < numInputs; i++)     //from 0 to max number
{
while (!success)                   //while no valid number
{
try {
numbers[i] = keyboard.nextInt();    //fill the current cell with a number
numberChecker(numbers[i]);          //is it valid?
success = true;                     //ok
} catch (Exception e)                     //else get a new number
{
keyboard.nextLine();
System.out.println("Whole numbers 0 through 9 only, please.");
}
}
success = false;
}
//for cells not used
for (int i = numInputs; i < numbers.length; i++) {
numbers[i] = 10;    //fill with garbage data (to prevent false positive 0s)
}
//take the input and count each use of element
for (int i : numbers)  //for 0 to max number
{
temp = i;  //get the current value of the cell
count[temp]++;      //add the use of that value to a new array's cell
}
System.out.println("Number Occurrence");
for (int i = 0; i < count.length; i++)   //from 0 to 9 (expected)
{
if ((count[i] > 0) && (count[i] <= 9))  //if cell not empty and has valid data
{
System.out.println(i + " " + count[i]);  //print the current cell and how many times it was used
}
}
System.out.println();   //spacer
//histogram segment
//find the highest-used number
for (int i : count)             //for each number
{
if(i > maximum)             //if greater than the current max
{
maximum = i;            //set to max
}
}
System.out.println("========= Vertical Bar ========");
for (int i = maximum; i > 0; i--)        //max through 1
{
if ((count[i] > 0) && (count[i] <=9))   //if has valid data
{
System.out.print((i) + "\t | ");      // print the number and a nice line for readability
for (int j = 0; j < count.length; j++)      //for the number of times that number was used
{
if ((count[j] > 0) && (count[j] <=9))   //if has valid data
{
if (count[j] >= i)                  //if that number the max
{
System.out.print("* ");            //print an asterisk
}
else
{
System.out.print("  ");     //"skip" and keep alignment
}
}
}
System.out.println();                   //make a new line
}
}
System.out.println("===============================");  //footer
System.out.println("| No | 0 1 2 3 4 5 6 7 8 9");
System.out.println("===============================");
}
static void numInputChecker(int integer) throws Exception
{
if ((integer < 1) || (integer > 30))    //if 0 or negative, or if 31+
{
throw new Exception();              //say no
}
}
static void numberChecker(int integer) throws Exception
{
if ((integer < 0) || (integer > 9)) //if negative or 10+
{
throw new Exception();          //say no
}
}
}
</details>
# 答案1
**得分**: 1
你的问题在于你在星号输出逻辑中有太多的`if`块。根据数据，在某些水平位置上你决定不打印任何内容，但实际上你想要做的是在每个水平位置上打印两个字符（要么是一个空格加一个星号，要么是两个空格），而不管在该位置是否看到任何数字。因此，如果你去掉所有的`if`块，只保留一个`if`块，你的打印代码会变得更简单，并且会得到正确的结果：
```java
System.out.println("========= Vertical Bar ========");
// 对于每个计数，从最大值开始...
for (int i = maximum; i > 0; i--) {
System.out.print((i) + "\t | ");
// 对于从0到最大数字的每个数字
for (int j = 0; j < count.length; j++) {
// 如果在此水平位置的计数大于或等于垂直计数（我们所在的行号），则打印一个星号，否则打印一个空格。
if (count[j] >= i) {
System.out.print("* ");
} else {
System.out.print("  ");
}
}
System.out.println();
}
System.out.println("==============================");
System.out.println("| No | 0 1 2 3 4 5 6 7 8 9");
System.out.println("==============================");

以下是我用于测试的一个相当复杂的结果：

输入：

int[] numbers = { 1, 2, 3, 4, 5, 1, 1, 3, 3, 5, 5, 3, 3, 5, 5, 7 };

结果：

Number Occurrence
1 3
2 1
3 5
4 1
5 5
7 1
========= Vertical Bar ========
5	 |       *   *                                                   
4	 |       *   *                                                   
3	 |   *   *   *                                                   
2	 |   *   *   *                                                   
1	 |   * * * * *   *                                               
==============================
| No | 0 1 2 3 4 5 6 7 8 9
==============================

System.out.println("========= Vertical Bar ========");
// for each count, starting from the max...
for (int i = maximum; i > 0; i--) 
{
System.out.print((i) + "\t | ");          
// for each number from 0 to the largest number we saw
for (int j = 0; j < count.length; j++) 
{
// If the count at this position horizontally is greater than or
// equal to the count vertically (the line number we're on), then
// print an asterisk, else print a blank space.
if (count[j] >= i).   
{                    
System.out.print("* ");           
}
else
{
System.out.print("  ");           
}
}
System.out.println();                  
}
System.out.println("===============================");
System.out.println("| No | 0 1 2 3 4 5 6 7 8 9");
System.out.println("===============================");

int[] numbers = { 1, 2, 3, 4, 5, 1, 1, 3, 3, 5, 5, 3, 3, 5, 5, 7 };

Number Occurrence
1 3
2 1
3 5
4 1
5 5
7 1
========= Vertical Bar ========
5	 |       *   *                                                   
4	 |       *   *                                                   
3	 |   *   *   *                                                   
2	 |   *   *   *                                                   
1	 |   * * * * *   *                                               
===============================
| No | 0 1 2 3 4 5 6 7 8 9
===============================

答案2

得分: 0

import java.util.Scanner;

public class Histogram
{
    public static void main(String[] args)
    {
        //variables
        Scanner keyboard = new Scanner(System.in);
        int numInputs = 1, temp, maximum = 0;
        int[] numbers = new int[31];
        int[] count = new int[31];
        boolean success = false;

        //start of program
        System.out.println("How many input values [max:30]?");

        //while no valid input
        while (!success)
        {
            try
            {
                numInputs = keyboard.nextInt(); //get a number
                numInputChecker(numInputs);     //is it valid?
                success = true;                 //ok

            } catch (Exception e)                 //else get a new number
            {
                keyboard.nextLine();
                System.out.println("Whole numbers 1 through 30 only, please.");

            }
        }
        //reset the loop checker
        success = false;

        //read numbers to fill that array
        System.out.println("Enter " + numInputs + " numbers.");

        for (int i = 0; i < numInputs; i++)     //from 0 to max number
        {
            while (!success)                   //while no valid number
            {
                try
                {
                    numbers[i] = keyboard.nextInt();    //fill the current cell with a number
                    numberChecker(numbers[i]);          //is it valid?
                    success = true;                     //ok
                } catch (Exception e)                   //else get a new number
                {
                    keyboard.nextLine();
                    System.out.println("Whole numbers 0 through 9 only, please.");
                }
            }
            success = false;
        }

        //for cells not used
        for (int i = numInputs; i < numbers.length; i++)
        {
            numbers[i] = -1;    //fill with garbage data (to prevent false positive 0s)
        }

        //take the input and count each use of element
        for (int i : numbers)  //for 0 to max number
        {
            if (i != -1)       //if valid data
            {
                temp = i;           //get the current value of the cell
                count[temp]++;      //add the use of that value to a new array's cell
            }

        }

        System.out.println("Number Occurrence");

        for (int i = 0; i < count.length; i++)   //from 0 to 9 (expected)
        {
            if (count[i] > 0)  //if cell has valid data
            {
                System.out.println(i + " " + count[i]);  //print the current cell and how many times it was used
            }
        }
        System.out.println();   //spacer

        //histogram segment

        //find the highest-used number
        for (int k : count)              //for 0 to 9
        {
            if (k > maximum)             //if greater than the current max
            {
                maximum = k;             //set to max
            }
        }

        System.out.println("========= Vertical Bar ========");

        for (int i = maximum; i > 0; i--) // from max to 1
        {
            System.out.print((i) + "\t | ");    //print the number and a spacer for visibility


            for (int j = 0; j < count.length; j++)   // from 0 to max
            {

                    if (count[j] >= i)                    // If the count at this position horizontally is greater than or
                                                          // equal to the count vertically (the line number we're on)
                    {
                        System.out.print("* ");           //print an asterisk
                    }
                    else
                        {
                            System.out.print("  ");       //else print a blank
                        }
            }
            System.out.println();                         //spacer
        }
        //footer
        System.out.println("===============================");
        System.out.println("| No | 0 1 2 3 4 5 6 7 8 9");
        System.out.println("===============================");
        }

    static void numInputChecker(int integer) throws Exception
    {
        if ((integer < 1) || (integer > 30))    //if 0 or negative, or if 31+
        {
            throw new Exception();              //say no
        }
    }

    static void numberChecker(int integer) throws Exception
    {
        if ((integer < 0) || (integer > 9)) //if negative or 10+
        {
            throw new Exception();          //say no
        }
    }

}

public class Histogram
{
public static void main(String[] args)
{
//variables
Scanner keyboard = new Scanner(System.in);
int numInputs = 1, temp, maximum = 0;
int[] numbers = new int[31];
int[] count = new int[31];
boolean success = false;
//start of program
System.out.println("How many input values [max:30]?");
//while no valid input
while (!success)
{
try
{
numInputs = keyboard.nextInt(); //get a number
numInputChecker(numInputs);     //is it valid?
success = true;                 //ok
} catch (Exception e)                 //else get a new number
{
keyboard.nextLine();
System.out.println("Whole numbers 1 through 30 only, please.");
}
}
//reset the loop checker
success = false;
//read numbers to fill that array
System.out.println("Enter " + numInputs + " numbers.");
for (int i = 0; i < numInputs; i++)     //from 0 to max number
{
while (!success)                   //while no valid number
{
try
{
numbers[i] = keyboard.nextInt();    //fill the current cell with a number
numberChecker(numbers[i]);          //is it valid?
success = true;                     //ok
} catch (Exception e)                   //else get a new number
{
keyboard.nextLine();
System.out.println("Whole numbers 0 through 9 only, please.");
}
}
success = false;
}
//for cells not used
for (int i = numInputs; i < numbers.length; i++)
{
numbers[i] = -1;    //fill with garbage data (to prevent false positive 0s)
}
//take the input and count each use of element
for (int i : numbers)  //for 0 to max number
{
if (i != -1)       //if valid data
{
temp = i;           //get the current value of the cell
count[temp]++;      //add the use of that value to a new array's cell
}
}
System.out.println("Number Occurrence");
for (int i = 0; i < count.length; i++)   //from 0 to 9 (expected)
{
if (count[i] > 0)  //if cell has valid data
{
System.out.println(i + " " + count[i]);  //print the current cell and how many times it was used
}
}
System.out.println();   //spacer
//histogram segment
//find the highest-used number
for (int k : count)              //for 0 to 9
{
if (k > maximum)             //if greater than the current max
{
maximum = k;             //set to max
}
}
System.out.println("========= Vertical Bar ========");
for (int i = maximum; i > 0; i--) // from max to 1
{
System.out.print((i) + "\t | ");    //print the number and a spacer for visibility
for (int j = 0; j < count.length; j++)   // from 0 to max
{
if (count[j] >= i)                    // If the count at this position horizontally is greater than or
// equal to the count vertically (the line number we're on)
{
System.out.print("* ");           //print an asterisk
}
else
{
System.out.print("  ");       //else print a blank
}
}
System.out.println();                         //spacer
}
//footer
System.out.println("===============================");
System.out.println("| No | 0 1 2 3 4 5 6 7 8 9");
System.out.println("===============================");
}
static void numInputChecker(int integer) throws Exception
{
if ((integer < 1) || (integer > 30))    //if 0 or negative, or if 31+
{
throw new Exception();              //say no
}
}
static void numberChecker(int integer) throws Exception
{
if ((integer < 0) || (integer > 9)) //if negative or 10+
{
throw new Exception();          //say no
}
}
}