[Python, HackerRank] Plus Minus

Plus Minus | HackerRank

주어진 문제

Given an array of integers, calculate the ratios of its elements that are positive, negative, and zero. 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 10^(-4) are acceptable.

Example

arr = [1,1,0,-1,-1]
There are n = 5 elements, two positive, two negative and one zero.
Their ratios are 2/5 = 0.400000, 2/5 = 0.400000 and 1/5 = 0.200000. Results are printed as:

0.400000
0.400000
0.200000

Function Description

Complete the plusMinus function in the editor below.
plusMinus has the following parameter(s):

• int arr[n]: 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 6 digits after the decimal. The function should not return a value.

Input Format

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

Constraints
0 < n <= 100

-100 <= arr[i] <=100

 

Output Format

Print the following 3 lines, each to 6 decimals:

1. proportion of positive values
2. proportion of negative values
3. proportion of zeros

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

 

Explanation

There are 3 positive numbers, 2 negative numbers, and 1 zero in the array.
The proportions of occurrence are positive: 3/6 = 0.500000, negative: 2/6 = 0.333333 and zeros: 1/6 = 0.166667.

결과 값을 소수점으로 표현하고 n번째 자리수에서 자르기

# 유리수, '.(자릿수)f'
format(float_number,'.(n)f'))

def plusMinus(arr):
    # Write your code here
    plus, minus, zero = 0, 0, 0
    
    for i in arr :
        if i < 0 :
            minus += 1
        elif i == 0 :
            zero += 1
        else : 
            plus += 1
    
    print(format(plus/len(arr),'.6f'))
    print(format(minus/len(arr),'.6f'))
    print(format(zero/len(arr),'.6f'))

 

GitHub - SVB-algorithm-study/JuniPark: SVB

 

참조 :
https://code-code.tistory.com/10