2010-05-08 26 views
10
Scanner scan = new Scanner(System.in); 
double numbers = scan.nextDouble(); 
double[] avg =..???? 
+0

這是已知或未知的條目數量? – Bozho 2010-05-08 19:45:23

回答

19

你可以嘗試這樣的事情:

public static void main (String[] args) 
{ 
    Scanner input = new Scanner(System.in); 
    double[] numbers = new double[5]; 

    for (int i = 0; i < numbers.length; i++) 
    { 
     System.out.println("Please enter number"); 
     numbers[i] = input.nextDouble(); 
    } 
} 

似乎很基本的東西,除非我誤解你

+0

當你檢查數組容量(5)時,這將不起作用。更好的選擇是使用List。 – 2016-10-07 06:37:06

+0

@MarkHughes:確實,但OP要求一個數組。 – npinti 2016-10-10 05:35:07

+0

那就是爲什麼我把它作爲評論而不是答案。這些問題通常出現在搜索結果中:) – 2016-10-10 05:41:06

0
double [] avg = new double[5]; 
for(int i=0; i<5; i++) 
    avg[i] = scan.nextDouble(); 
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可以說5條目 – 2010-05-08 19:39:12

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@WM編輯答案.. – Feyyaz 2010-05-08 19:44:03

6

你可以得到所有與此代碼雙打:

List<Double> numbers = new ArrayList<Double>(); 
while (scan.hasNextDouble()) { 
    numbers.add(scan.nextDouble()); 
} 
+0

如何將字符串添加到'List',我使用此代碼'while(scanner.hasNext()){ \t \t list.add(scanner.next ).toString());}'但它給了我'NullPointerException' – 2016-06-02 17:15:37

0
Scanner scan = new Scanner (System.in); 

for (int i=0; i<=4, i++){ 

    System.out.printf("Enter value at index"+i+" :"); 

    anArray[i]=scan.nextInt(); 

} 
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您還應該顯示數組的聲明? – 2012-10-26 06:50:40

3
import java.util.Scanner; 

public class Main { 
    /** 
    * @param args 
    */ 
    public static void main(String[] args) { 
     Scanner in=new Scanner (System.in); 
     int num[]=new int[10]; 
     int average=0; 
     int i=0; 
     int sum=0; 

     for (i=0;i<num.length;i++) { 
      System.out.println("enter a number"); 
      num[i]=in.nextInt(); 
      sum=sum+num[i]; 
     } 
     average=sum/10; 
     System.out.println("Average="+average); 
    } 
} 
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這可用於獲得輸入的平均值 – 2016-06-02 03:13:44

1
import java.util.Scanner; 

class Array { 
public static void main(String a[]){ 

    Scanner input = new Scanner(System.in); 

    System.out.println("Enter the size of an Array"); 

    int num = input.nextInt(); 

    System.out.println("Enter the Element "+num+" of an Array"); 

    double[] numbers = new double[num]; 

    for (int i = 0; i < numbers.length; i++) 
    { 

     System.out.println("Please enter number"); 

     numbers[i] = input.nextDouble(); 

    } 

    for (int i = 0; i < numbers.length; i++) 
    { 

     if ((i%3) !=0){ 

      System.out.print(""); 

      System.out.print(numbers[i]+"\t"); 

     } else { 
      System.out.println(""); 

      System.out.print(numbers[i]+"\t"); 
     } 

    } 

} 
2

下面的代碼:

import java.util.Scanner; 

    class Array { 
    public static void main(String a[]){ 

     Scanner input = new Scanner(System.in); 

     System.out.println("Enter the size of an Array"); 

     int num = input.nextInt(); 

     System.out.println("Enter the Element "+num+" of an Array"); 

     double[] numbers = new double[num]; 

     for (int i = 0; i < numbers.length; i++) 
     { 

      System.out.println("Please enter number"); 

      numbers[i] = input.nextDouble(); 

     } 

     for (int i = 0; i < numbers.length; i++) 
     { 

      if ((i%3) !=0){ 

       System.out.print(""); 

       System.out.print(numbers[i]+"\t"); 

      } else { 
       System.out.println(""); 

       System.out.print(numbers[i]+"\t"); 
      } 

     } 

    } 

嘗試這樣想

0
import java.util.Scanner; 
public class sort { 

    public static void main(String args[]) 
    { 
     int i,n,t;   

     Scanner sc=new Scanner(System.in); 

     System.out.print("Enter the size of array"); 

     n=sc.nextInt(); 

     int a[] = new int[n]; 

     System.out.println("Enter elements in array"); 

     for(i=0;i<n;i++) 
     { 
      a[i]=sc.nextInt(); 
     } 
     t=a[1]; 

     for(i=0;i<n;i++) 
     { 
      if(a[i]>t) 

       t=a[i]; 
     } 
     System.out.println("Greates integer is" +t); 
    } 
} 
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儘管您的答案可能會解決問題,但如果您能夠提供問題描述以及答案如何解決問題,則總是更好。這是進一步改善這一點,未來的答案的建議。 – 2014-11-22 15:54:04

0

這是一個程序,以顯示如何從系統給出的輸入,並計算總和在每個級別和平均水平。

package NumericTest; 

import java.util.Scanner; 

public class SumAvg { 


public static void main(String[] args) { 

int i,n; 
System.out.println("Enter the number of inputs"); 
Scanner sc = new Scanner(System.in); 
n=sc.nextInt(); 
int a[] = new int [n]; 

    System.out.println("Enter the inputs"); 
    for(i=0;i<n;i++){ 
    a[i] = sc.nextInt(); 
    System.out.println("Inputs are " +a[i]); 
} 

    int sum = 0; 
    for(i=0;i<n;i++){ 
sum = sum +a[i]; 
    System.out.println("Sums : " +sum); 
} 
    int avg ; 
    avg = sum/n; 
    System.out.println("avg : " +avg); 
    } 
}