查找值的位置的二維陣列上在Java

Question

我有輸入值爲我的2D陣列，即5由2的尺寸。 我有一列上的每個數字的出現次數。 和另一列上的每個數字

我找到了出現次數的最大值，並且需要移動到2d數組中的值左側的單元格以根據出現次數打印出數字的值。 任何幫助將是偉大的！

我的代碼：

import java.util.Collections; 
import java.util.Scanner; 
import java.util.Arrays; 
import java.util.List; 

public class Code { 

    public static void main(String[] args) { 
     int num1, num2, num3, num4, num5, sum, avg, max, min; 

     Scanner keyboard = new Scanner(System.in); 
     System.out.println("Enter the first number:"); 
     num1 = keyboard.nextInt(); 
     System.out.println("Enter the seond number:"); 
     num2 = keyboard.nextInt(); 
     System.out.println("Enter the third number:"); 
     num3 = keyboard.nextInt(); 
     System.out.println("Enter the fourth number:"); 
     num4 = keyboard.nextInt(); 
     System.out.println("Enter the fifth number:"); 
     num5 = keyboard.nextInt(); 
     keyboard.close(); 

     int[] num = new int[5]; // array named num is declared with 5 variables 
     num[0] = num1; 
     num[1] = num2; 
     num[2] = num3; 
     num[3] = num4; 
     num[4] = num5; 
     Arrays.sort(num); 

     int n1 = num[0]; 
     int n2 = num[1]; 
     int n3 = num[2]; 
     int n4 = num[3]; 
     int n5 = num[4]; 

     List<Integer> index1 = Arrays.asList(n1, n2, n3, n4, n5); 
     int occurrences1 = Collections.frequency(index1, n1); 

     List<Integer> index2 = Arrays.asList(n1, n2, n3, n4, n5); 
     int occurrences2 = Collections.frequency(index2, n2); 

     List<Integer> index3 = Arrays.asList(n1, n2, n3, n4, n5); 
     int occurrences3 = Collections.frequency(index3, n3); 

     List<Integer> index4 = Arrays.asList(n1, n2, n3, n4, n5); 
     int occurrences4 = Collections.frequency(index4, n4); 

     List<Integer> index5 = Arrays.asList(n1, n2, n3, n4, n5); 
     int occurrences5 = Collections.frequency(index5, n5); 

     int[][] nums = new int[5][2]; 
     nums[0][0] = n1; 
     nums[1][0] = n2; 
     nums[2][0] = n3; 
     nums[3][0] = n4; 
     nums[4][0] = n5; 
     nums[0][1] = occurrences1; 
     nums[1][1] = occurrences2; 
     nums[2][1] = occurrences3; 
     nums[3][1] = occurrences4; 
     nums[4][1] = occurrences5; 

     int maxOccurrences = Math.max(Math.max(Math.max(Math.max(occurrences1, occurrences2), occurrences3), occurrences4), occurrences5); 
     System.out.println(maxOccurrences); 

     sum = (int) (num1 + num2 + num3 + num4 + num5); 
     avg = (int) (sum/5); 
     max = Math.max(Math.max(Math.max(Math.max(num1, num2), num3), num4), num5); 
     min = Math.min(Math.min(Math.min(Math.min(num1, num2), num3), num4), num5); 

     System.out.println(" "); 
     System.out.println("Sum:" + sum); 
     System.out.println("Avg:" + avg); 
     System.out.println("Max:" + max); 
     System.out.println("Min:" + min); 
     System.out.println("Median:" + num[2]); 
     System.out.println("Mode:" + min); 

    } 
} 

Answer 1

我認爲一個二維數組是不是最優雅的數據結構要達到的目標。它看起來像一個TreeMap可能適合在這裏，但這只是一個猜測。

在任何情況下，閱讀這些資源：

• 關於數組：http://docs.oracle.com/javase/tutorial/java/nutsandbolts/arrays.html
• 關於for循環：http://docs.oracle.com/javase/tutorial/java/nutsandbolts/for.html

想象一下，你不得不延長當前的代碼，以支持更多超過5個輸入值！

import java.util.Arrays; 
import java.util.Comparator; 
import java.util.Scanner; 

public class Occurances 
{ 
    public static void main(String[] args) 
    { 
     int numNums = 5; 

     int[][] num = new int[numNums][2]; 

     Scanner keyboard = new Scanner(System.in); 
     for (int i=0; i<numNums; i++) 
     { 
      System.out.println("Enter the "+i+"th number:"); 
      num[i][0] = keyboard.nextInt(); 
      //num[i][0] = (i*i)%numNums; 
      //System.out.println("Number "+i+" is "+num[i][0]); 
     } 
     keyboard.close(); 

     sort(num, 0); 

     int maxOccurrences = -1; 
     for (int i=0; i<numNums; i++) 
     { 
      num[i][1] = computeFrequency(num[i][0], num, 0); 

      maxOccurrences = Math.max(maxOccurrences, num[i][1]); 
     } 

     System.out.println("maxOccurrences "+maxOccurrences); 

     int sum = computeSum(num, 0); 
     int avg = sum/numNums; 
     int max = computeMax(num, 0); 
     int min = computeMin(num, 0); 

     System.out.println(" "); 
     System.out.println("Sum:" + sum); 
     System.out.println("Avg:" + avg); 
     System.out.println("Max:" + max); 
     System.out.println("Min:" + min); 
     System.out.println("Median:" + num[numNums/2][0]); 
     System.out.println("Mode:" + min); 
    } 

    private static int computeSum(int array[][], int column) 
    { 
     int sum = 0; 
     for (int i=0; i<array.length; i++) 
     { 
      sum += array[i][column]; 
     } 
     return sum; 
    } 

    private static int computeMin(int array[][], int column) 
    { 
     int min = Integer.MAX_VALUE; 
     for (int i=0; i<array.length; i++) 
     { 
      min = Math.min(min, array[i][column]); 
     } 
     return min; 
    } 

    private static int computeMax(int array[][], int column) 
    { 
     int max = Integer.MIN_VALUE; 
     for (int i=0; i<array.length; i++) 
     { 
      max = Math.max(max, array[i][column]); 
     } 
     return max; 
    } 

    private static void sort(int array[][], final int column) 
    { 
     Arrays.sort(array, new Comparator<int[]>() 
     { 
      @Override 
      public int compare(int[] a0, int[] a1) 
      { 
       return Integer.compare(a0[column], a1[column]); 
      } 
     }); 
    } 

    private static int computeFrequency(int value, int array[][], int column) 
    { 
     int count = 0; 
     for (int i=0; i<array.length; i++) 
     { 
      if (array[i][column] == value) 
      { 
       count++; 
      } 
     } 
     return count; 
    } 


}