[해커랭크] Plus Minus

https://www.hackerrank.com/challenges/plus-minus/problem?isFullScreen=true

Plus Minus | HackerRank

Given an array of integers, calculate the ratios of its elements that are , , and . Print the decimal value of each fraction on a new line with 6 places after the decimal.

Note: This challenge introduces precision problems. The test cases are scaled to six decimal places, though answers with absolute error of up to  are acceptable.

Example

There are  elements: two positive, two negative and one zero. Their ratios are ,  and . Results are printed as:

0.400000
0.400000
0.200000

Function Description

Complete the  function with the following parameter(s):

• : an array of integers

Print
Print the ratios of positive, negative and zero values in the array. Each value should be printed on a separate line with  digits after the decimal. The function should not return a value.

Input Format

The first line contains an integer, , the size of the array.
The second line contains  space-separated integers that describe .

Constraints

Sample Input

STDIN           Function
-----           --------
6               arr[] size n = 6
-4 3 -9 0 4 1   arr = [-4, 3, -9, 0, 4, 1]

Sample Output

0.500000
0.333333
0.166667

 

 

import java.io.*;

import java.math.*;

import java.security.*;

import java.text.*;

import java.util.*;

import java.util.concurrent.*;

import java.util.function.*;

import java.util.regex.*;

import java.util.stream.*;

import static java.util.stream.Collectors.joining;

import static java.util.stream.Collectors.toList;

class Result {

    /*

     * Complete the 'plusMinus' function below.

     *

     * The function accepts INTEGER_ARRAY arr as parameter.

     */

    public static void plusMinus(List<Integer> arr) throws IOException {

    // Write your code here

        int type[] = new int[3];    // + - 0

        for(Integer i : arr){

            if(i>0){

                type[0]++;

            }

            else if(i<0){

                type[1]++;

            }

            else if(i==0){

                type[2]++;

            }

            else{

                // except

                continue;

            }

        }

       

        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));

       

        String type0 = String.format("%.6f", (type[0]*1.0)/arr.size());

        String type1 = String.format("%.6f", (type[1]*1.0)/arr.size());

        String type2 = String.format("%.6f", (type[2]*1.0)/arr.size());

        bw.write(String.valueOf(type0));

        bw.newLine();

        bw.write(String.valueOf(type1));

        bw.newLine();

        bw.write(String.valueOf(type2));

        bw.close();

        return;

    }

}

public class Solution {

    public static void main(String[] args) throws IOException {

        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));

        int n = Integer.parseInt(bufferedReader.readLine().trim());

        List<Integer> arr = Stream.of(bufferedReader.readLine().replaceAll("\\s+$", "").split(" "))

            .map(Integer::parseInt)

            .collect(toList());

        Result.plusMinus(arr);

        bufferedReader.close();

    }

}