Tasks Details
Task description
Write a function
class Solution { public int solution(int[] A); }
that, given an array A consisting of N integers, returns the number of distinct values in array A.
For example, given array A consisting of six elements such that:
A[0] = 2 A[1] = 1 A[2] = 1 A[3] = 2 A[4] = 3 A[5] = 1the function should return 3, because there are 3 distinct values appearing in array A, namely 1, 2 and 3.
Write an efficient algorithm for the following assumptions:
- N is an integer within the range [0..100,000];
- each element of array A is an integer within the range [−1,000,000..1,000,000].
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Solution
Programming language used C#
Time spent on task 7 minutes
Notes
not defined yet
Task timeline
Code: 03:16:47 UTC,
cs,
final,
score:
100
using System;
using System.Collections;
// you can also use other imports, for example:
// using System.Collections.Generic;
// you can use Console.WriteLine for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(int[] A) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
var distinctNumbersCount = 0;
const int minNumber = -1000000;
const int maxNumber = 1000000;
var bitArray = new BitArray(maxNumber - minNumber + 1, false);
foreach (var element in A)
{
if (!bitArray[element + maxNumber])
{
bitArray[element + maxNumber] = true;
distinctNumbersCount += 1;
}
}
return distinctNumbersCount;
}
}Analysis summary
The solution obtained perfect score.
Analysis
Detected time complexity:
O(N) or O(N*log(N))