java - 我如何获得正确的输出来打印数组中正数、负数和零数的分数？

Question

这个问题已经有答案了:

Int division: Why is the result of 1/3 == 0? (19 个回答)

已关闭 4 年前。

public class Solution {
    public static void main(String[] args) {
        int ne = 0;
        int p = 0;
        int z = 0;
        Scanner in = new Scanner(System.in);
        int n = in .nextInt();
        int arr[] = new int[n];
        for (int arr_i = 0; arr_i < n; arr_i++) {
            arr[arr_i] = in .nextInt();
        }
        for (int arr_i = 0; arr_i < n; arr_i++) {
            if (arr[arr_i] > 0) {
                p++;
            } else if (arr[arr_i] < 0) {
                ne++;
            } else {
                z++;
            }
        }
        double n1 = p / n; // this is showing 0 ouput    
        double n2 = ne / n; // this is showing 0 ouput      
        double n3 = z / n; // this is showing 0 ouput    
        System.out.println(n1);
        System.out.println(n2);
        System.out.println(n3);
    }
}

问题是打印正数、负数和零与数组中元素数量的分数。输出显示所有内容均为 0，请指出错误

Answer 1

使用下面的代码。您正在进行整数除法，将结果四舍五入为 0。

double n1=((double)p)/n;    
double n2=((double)ne)/n;      
double n3=((double)z)/n;