Найти номер наибольшего и наименьшего чисел с помощью массивов

Question

Попытка позволить пользователям ввести число целых чисел, чтобы я мог установить длину массива, а затем найти максимальное и минимальное значение. Однако я не могу найти max и min. Пожалуйста помоги.

import java.util.Scanner; 
import java.util.Arrays; 
public class ExerciseC{ 
    public static void main(String[] args){ 
     Scanner keyboard = new Scanner(System.in); 
     System.out.println("Enter the number of integers you would like to enter:"); 
     int numberEnter = keyboard.nextInt(); 
     System.out.println("Enter some integers:"); 
     int integers = keyboard.nextInt(); 
     int numbers [] = new int [numberEnter]; 
     int maxValue = numbers[0]; 
     int minValue = numbers[0]; 
     int max = 0; 
     int min = 0; 
     for (int index = 1; index < numbers.length; index ++) { 
      if (numbers[index] > maxValue) { 
       maxValue = numbers [index]; 
      } 
     } 
     System.out.println("Print: " + maxValue); 
     System.out.println("The difference between the largest and the smallest is: "); 
    } 

} 

Answer 1

Вам не кажется, что ввод более одного значения (и вы никогда не храните integers в массиве). Кроме того, вы не устанавливаете мин. Я думаю, что вы хотели

public static void main(String[] args) { 
    Scanner keyboard = new Scanner(System.in); 
    System.out.println("Number of integers to enter:"); 
    int numberEnter = keyboard.nextInt(); 
    int numbers[] = new int[numberEnter]; 
    int pos = 0; 
    do { 
     System.out.printf("Please enter integer #%d/%d:%n", pos, numberEnter); 
     numbers[pos++] = keyboard.nextInt(); 
    } while (pos < numberEnter && keyboard.hasNextInt()); 
    int min = numbers[0]; 
    int max = numbers[0]; 
    for (pos = 1; pos < numbers.length; pos++) { 
     if (numbers[pos] < min) { // <-- test min. 
      min = numbers[pos]; 
     } 
     if (numbers[pos] > max) { // <-- test max. 
      max = numbers[pos]; 
     } 
    } 
    // Display everything. 
    System.out.printf("%s Min: %d Max: %d%n", Arrays.toString(numbers), 
      min, max); 
} 

Answer 2

Ваш numbers[] пуст. Вход пользователя не сохраняется в массиве.

Вот ваш фиксированный код:

package com.company; 

import java.util.Scanner; 

public class ExerciseC{ 
    public static void main(String[] args){ 
     Scanner keyboard = new Scanner(System.in); 
     System.out.println("Enter the number of integers you would like to enter:"); 
     int numberEnter = keyboard.nextInt(); 
     int numbers [] = new int [numberEnter]; 
     for (int i = 0; i < numberEnter; i++) { 
      System.out.println("Enter integer:"); 
      numbers[i] = keyboard.nextInt(); 
     } 
     int maxValue = numbers[0]; 
     int minValue = numbers[0]; 
     for (int index = 1; index < numbers.length; index ++) { 
      if (numbers[index] > maxValue) { 
       maxValue = numbers [index]; 
      } 
     } 
     System.out.println("Print: " + maxValue); 
     System.out.println("The difference between the largest and the smallest is: "); 
    } 

} 

Answer 3

import java.util.Scanner; 
    class StdR { 
public static void main(String[] args) { 
     // TODO Auto-generated method stub 

     StdR st = new StdR(); 
     st.stdR(); 
     //System.out.println(st.stdR(); 
    } 
     void stdR() 
     { 
      char[] grade = {'A','B','C','D','E','F'}; 
      Scanner input = new Scanner(System.in); 
      byte[] st = new byte[3]; 
      double[] percentage = new double[st.length]; 

      for(byte s = 0; s < st.length; s++){ 
       System.out.println("\nStudent " + s); 
       short noOfMarks = 0; 
       short totalMarks = 450; 
       percentage[s] = 0.0; 
       byte[] marks = new byte[5]; 

       for (byte i = 0; i < marks.length; i++){ 

        System.out.println("Enter marks of Chapter "+ i + ": "); 
        marks[i] = input.nextByte(); 

        noOfMarks += marks[i]; 
        percentage[s] += (marks[i] * 100)/totalMarks; 
       } 

       System.out.print("No of marks: " + noOfMarks + "\t"); 
       System.out.print("Percentage: " + percentage[s] + "\t"); 
       if (percentage[s] > 79.0 && percentage[s] < 100.1) 
        System.out.print("Grade: " + grade[0]); 
       else if (percentage[s] > 69.0 && percentage[s] < 80.0) 
        System.out.print("Grade: " + grade[1]); 
       else if (percentage[s] > 59.0 && percentage[s] < 70.0) 
        System.out.print("Grade: " + grade[2]); 
       else if (percentage[s] > 49.0 && percentage[s] < 60.0) 
        System.out.print("Grade: " + grade[3]); 
       else if (percentage[s] > 39.0 && percentage[s] < 50.0) 
        System.out.print("Grade: " + grade[4]); 
       else if (percentage[s] < 40.0) 
        System.out.print("Grade: " + grade[5]); 
      } 
      double smallest = percentage[0] , largest= percentage[0]; 

      for (int i=0 ;i< percentage.length; i++) { 
       if (percentage[i] < smallest) { 
        smallest = percentage[i]; 
       } // end finding smallest 
       if (percentage[i] > largest) { 
        largest = percentage[i]; 
       } 

      } 
      System.out.println("\n1st Position and Top percentage is " + largest); 
      System.out.println("\nLast Position and Least percentage is "+smallest); 
     } 
    }