C++ STL Set 8 (unordered set).cpp

//{ Driver Code Starts
#include <bits/stdc++.h>
using namespace std;

void insert(unordered_set<int> &s, int x);

void erase(unordered_set<int> &s, int x);
int size(unordered_set<int> &s);
int find(unordered_set<int> &s, int x);

int main()
{
    // your code goes here
    int t;
    cin >> t;
    while (t--)
    {
        unordered_set<int> s;
        int q;
        cin >> q;
        while (q--)
        {
            char c;
            cin >> c;
            if (c == 'a')
            {
                int x;
                cin >> x;
                insert(s, x);
            }

            if (c == 'b')
            {
                int x;
                cin >> x;
                erase(s, x);
            }
            if (c == 'c')
            {
                int x;
                cin >> x;
                cout << find(s, x) << " ";
            }
            if (c == 'd')
                cout << size(s) << " ";
        }
        cout << endl;
    }
    return 0;
}
// } Driver Code Ends

/* You are required to complete below methods */

/*inserts an element x to the unordered set s */
void insert(unordered_set<int> &s, int x)
{
    s.insert(x);
}

/*erases an element x from the unordered set s */
void erase(unordered_set<int> &s, int x)
{
    s.erase(x);
}

/*returns the size of the unordered set s */
int size(unordered_set<int> &s)
{
    return s.size();
}

/*returns 1 if the element x is present
in unordered set s else returns -1 */
int find(unordered_set<int> &s, int x)
{
    if (s.find(x) != s.end())
    {
        return 1;
    }
    else
    {
        return -1;
    }
}