#include<bits/stdc++.h>

using namespace std;

class Solution {

public:

int removeDuplicates(vector<int>& nums) {

/*

TLE

Time complexity: 0(n*m): Because we are using `find` function in the loop.

int cnt = 0;

vector<int> result;

for (int i=0; i<nums.size(); i++) {

if (find(result.begin(), result.end(), nums[i]) == result.end()) {

result.push_back(nums[i]);

cnt++;

}

}

for (int i=0; i<result.size(); i++) {

nums[i] = result[i];

}

return cnt; */

// create set to store unique elements

set<int> s;

// add values to set

for (int val : nums) {

s.insert(val);

}

// size of unique elements of set

int k = s.size();

int j = 0;

// Insert values back to vector

for (int val : s) {

nums[j++] = val;

}

return k;

}

};

int main() {

Solution sol;

vector<int> nums = {-1, 0, 0, 2, 3, 3, 4, 5, 9};

sol.removeDuplicates(nums);

for (int x : nums) {

cout << x << ", ";

}

}