Tasks Details
easy
1.
Distinct
Compute number of distinct values in an array.
Task Score
100%
Correctness
100%
Performance
100%
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].
Copyright 2009–2025 by Codility Limited. All Rights Reserved. Unauthorized copying, publication or disclosure prohibited.
Solution
Programming language used C#
Time spent on task 4 minutes
Notes
not defined yet
Task timeline
Code: 19:13:51 UTC,
cs,
verify,
result: Failed
using System;
// you can also use other imports, for example:
using System.Collections.Generic;
using System.Linq;
// 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)
int [] newA = A.Distinct().ToArray();
if (Al.Length <=0) return 0;
else return newA.Length;
}
}
Analysis
Compile error
Compilation failed: 1 error(s), 0 warnings Solution.cs(13,13): error CS0103: The name `Al' does not exist in the current context
Code: 19:14:06 UTC,
cs,
verify,
result: Passed
using System;
// you can also use other imports, for example:
using System.Collections.Generic;
using System.Linq;
// 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)
int [] newA = A.Distinct().ToArray();
if (A.Length <=0) return 0;
else return newA.Length;
}
}
Analysis
Code: 19:14:12 UTC,
cs,
verify,
result: Passed
using System;
// you can also use other imports, for example:
using System.Collections.Generic;
using System.Linq;
// 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)
int [] newA = A.Distinct().ToArray();
if (A.Length <=0) return 0;
else return newA.Length;
}
}
Analysis
Code: 19:14:15 UTC,
cs,
final,
score:
100
using System;
// you can also use other imports, for example:
using System.Collections.Generic;
using System.Linq;
// 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)
int [] newA = A.Distinct().ToArray();
if (A.Length <=0) return 0;
else return newA.Length;
}
}Analysis summary
The solution obtained perfect score.
Analysis
Detected time complexity:
O(N) or O(N*log(N))
expand all
Correctness tests
1.
0.089 s
OK
1.
0.090 s
OK
2.
0.086 s
OK
1.
0.098 s
OK
1.
0.093 s
OK
1.
0.090 s
OK
1.
0.087 s
OK
1.
0.093 s
OK
1.
0.093 s
OK
1.
0.091 s
OK