java.lang.Object
g1001_1100.s1093_statistics_from_a_large_sample.Solution

public class Solution extends java.lang.Object
1093 - Statistics from a Large Sample.

Medium

You are given a large sample of integers in the range [0, 255]. Since the sample is so large, it is represented by an array count where count[k] is the number of times that k appears in the sample.

Calculate the following statistics:

  • minimum: The minimum element in the sample.
  • maximum: The maximum element in the sample.
  • mean: The average of the sample, calculated as the total sum of all elements divided by the total number of elements.
  • median:
    • If the sample has an odd number of elements, then the median is the middle element once the sample is sorted.
    • If the sample has an even number of elements, then the median is the average of the two middle elements once the sample is sorted.
  • mode: The number that appears the most in the sample. It is guaranteed to be unique.

Return the statistics of the sample as an array of floating-point numbers [minimum, maximum, mean, median, mode]. Answers within 10-5 of the actual answer will be accepted.

Example 1:

Input: count = [0,1,3,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]

Output: [1.00000,3.00000,2.37500,2.50000,3.00000]

Explanation: The sample represented by count is [1,2,2,2,3,3,3,3].

The minimum and maximum are 1 and 3 respectively.

The mean is (1+2+2+2+3+3+3+3) / 8 = 19 / 8 = 2.375.

Since the size of the sample is even, the median is the average of the two middle elements 2 and 3, which is 2.5.

The mode is 3 as it appears the most in the sample.

Example 2:

Input: count = [0,4,3,2,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]

Output: [1.00000,4.00000,2.18182,2.00000,1.00000]

Explanation: The sample represented by count is [1,1,1,1,2,2,2,3,3,4,4].

The minimum and maximum are 1 and 4 respectively.

The mean is (1+1+1+1+2+2+2+3+3+4+4) / 11 = 24 / 11 = 2.18181818… (for display purposes, the output shows the rounded number 2.18182).

Since the size of the sample is odd, the median is the middle element 2.

The mode is 1 as it appears the most in the sample.

Constraints:

  • count.length == 256
  • 0 <= count[i] <= 109
  • 1 <= sum(count) <= 109
  • The mode of the sample that count represents is unique.
  • Constructor Summary

    Constructors
    Constructor
    Description
     
  • Method Summary

    Modifier and Type
    Method
    Description
    double[]
    sampleStats(int[] count)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Constructor Details

    • Solution

      public Solution()
  • Method Details

    • sampleStats

      public double[] sampleStats(int[] count)