lakhanamdhari / distinct

Compute number of distinct values in an array.

Distinct

Compute number of distinct values in an array.

Write a function

int solution(int A[], int N);

that, given a zero-indexed array A consisting of N integers, returns the number of distinct values in array A.

Assume that:

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]. 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] = 1 the function should return 3, because there are 3 distinct values appearing in array A, namely 1, 2 and 3.

Complexity:

expected worst-case time complexity is O(N*log(N)); expected worst-case space complexity is O(N), beyond input storage (not counting the storage required for input arguments). Elements of input arrays can be modified.