Round Price, Java - rextester

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//'main' method must be in a class 'Rextester'.
//Compiler version 1.8.0_111

import java.util.*;
import java.lang.*;

class Rextester
{  
    public static void main(String args[])
    {
        double[] input = new double[10];
        StringBuilder sb = new StringBuilder();
        Random rand = new Random();
        for (int i = 0; i < 10; i++) {
            int num1 = rand.nextInt(100);
            double num2 = rand.nextDouble();
            double num = (double) num1 + num2;
            input[i] = num;
            sb.append(num).append(",");
        }
        System.out.println(sb.toString());
        sb.setLength(0);
        int[] result = roundUp(input);
        for (int i = 0; i < result.length; i++) {
            sb.append(result[i]).append(",");
        }
        System.out.println(sb.toString());
    }
    
    public static int[] roundUp(double[] input) {
        double sum = 0;
        for (double i: input) sum += i;
        long target = Math.round(sum);
        //System.out.println("target = " + String.valueOf(target));
        
        long floorSum = 0;
        for (double i: input) floorSum += Math.round(Math.floor(i));
        
        List<NumberIndex> nums = new ArrayList<>();
        for (int i = 0; i < input.length; i++) nums.add(new NumberIndex(input[i], i));
        Collections.sort(nums, (a, b) -> (Math.ceil(a.val) - a.val) >= (Math.ceil(b.val) - b.val) ? 1 : -1);
        
        int[] res = new int[input.length];
        long diff = target - floorSum;
        for (NumberIndex num: nums) {
            if (diff-- > 0) res[num.index] = (int) Math.round(Math.ceil(num.val));
            else res[num.index] = (int) Math.round(Math.floor(num.val));
        }
        
        //int resSum = 0;
        //for (int num: res) resSum += num;
        //System.out.println("result = " + String.valueOf(resSum));
        return res;
    }
}

class NumberIndex {
    double val;
    int index;
    
    public NumberIndex(double v, int i) {
        val = v;
        index = i;
    }
}

[ + ] Show input
Compilation time: 1.03 sec, absolute running time: 0.28 sec, cpu time: 0.4 sec, memory peak: 25 Mb, absolute service time: 1,32 sec