Question

（计算正数和负数并计算数字的平均值）写读取未指定数量的整数的程序确定了多少已读取正值和负值，并计算总值和平均值输入值（不包括零）。您的程序以输入0结束。显示平均值为浮点数。这是一个示例运行：

输入一个整数，输入结束，如果它是0：1 2 -1 3 0

积极数为3

否定数为1

总数为5.0

平均值为1.25

我有两个主要问题。 1）我无法让循环停止。 2）即使我这样做，平均值也很短。使用上面的例子，我的平均值总是1.0，而不是1.25。就像程序正在读取总共5个数字而不是等于5的4个数字。下面的代码中可以看到的是我可以使用的全部内容：Java的基础知识......

import java.util.Scanner;

public class NewClass {
 public static void main(String[] args) {
 Scanner input = new Scanner(System.in);

     int positive = 0, negative = 0, total = 0, count = 0;

     float average;

     System.out.println("Enter the number: ");
     int number = input.nextInt();

     while(number != 0) {
        total += number;
        count++;

        if(number > 0){
        positive++;
        }

        else if(number < 0){
        negative++;
        }

     average = total / count;

     System.out.println("The number of positives is "+ positive);
     System.out.println("The number of negatives is "+ negative);
     System.out.println("The total is "+ total);
     System.out.println("The average is "+ average);
     }
   }
}

Answer 1

您需要阅读更多数字。你在循环之前读取了一个值。你可以做点什么

int number;
while((number = input.nextInt()) != 0) {
    total += number;
    count++;
    if(number > 0){
        positive++;
    } else if(number < 0) {
        negative++;
    }
} // <-- end loop body.
float average = total / (float) count; // <-- not integer math.
System.out.println("The number of positives is " + positive);
System.out.println("The number of negatives is " + negative);
System.out.println("The total is " + total);
System.out.println("The average is " + average);

Answer 2

你应该只使用do while。

import java.util.*;  
public class PosAndNeg   {   
public static void main(String [] args){  
Scanner input = new Scanner(System.in);  

int positive = 0, negative = 0, total = 0, count = 0;  
int number;
float average;

     System.out.println("Enter the number: ");
     do { number = input.nextInt();
     total += number;
        count++;  
           if(number > 0){
           positive++;
        }
             else if(number < 0){
            negative++;
        }
    }
     while(number != 0);

     average = total / count;

     System.out.println("The number of positives is "+ positive);
     System.out.println("The number of negatives is "+ negative);
     System.out.println("The total is "+ total);
     System.out.println("The average is "+ average);

    }

}

Answer 3

// use type conversion while evaluating average
import java.util.Scanner;
public class newClass{
public static void main(String[] args){
    int pos=0;
    int neg=0;
    int total=0;
Scanner sc= new Scanner(System.in);
System.out.println("enter the total numbers user want to enter");

int  i=sc.nextInt();
int [] num= new int[i];
System.out.println("Please enter number");
for (int j = 0; j < num.length; j++)
{   

    num[j] = sc.nextInt();
    if(num[j]>0)
        pos++;
    else
        neg++;
    total=total+num[j];

}
System.out.println(num.length);
double avg =(float)total/(num.length);
System.out.println("positive count="+pos+"negative count="+neg+" average ="+avg);
}
}

Answer 4

import java.util.Scanner;
public class NewClass{
public static void main(String[] args) {
    int N=0,p=0,t=0;
 System.out.println("enter 
integers");
Scanner obj=new Scanner 
(System.in);
    int a=obj.nextInt();
    while (a!=0){
    t+=a;
    if (a<0){
    N++;
    }
    else if (a>0){
    p++;
    }
    int b=obj.nextInt();
    a=b;
    }
    System.out.println("the 
    number of negative 
    numbers is\t\t"+N);
    System.out.println("the 
    number of positive number 
    is\t\t"+p);
    float l=N+p;
    float average=(float) t/l;
    System.out.println("the total 
    is\t\t"+t);
    System.out.println("the 
    average is\t\t"+average);
  }
}

编写一个读取未指定数量的整数的程序，确定pos，neg，total，average

4 个答案: