Description

• Dense Ranking

Submission 1

• O(m)
• Won’t work when the data size grows larger

This solution won’t pass some of the larger datasets since the O(nm)

vector<int> climbingLeaderboard(vector<int> scores, vector<int> alice) {
    vector<int> rank;
    rank.push_back(1);
    for(int i = 1, r = 1; i < scores.size(); ++i) {
        if(scores[i] == scores[i - 1]) {
            rank.push_back(r);
        } else {
            rank.push_back(++r);
        }
    }
    vector<int> res;
    for(auto a : alice) {
        if(a < *prev(scores.end())) {
            res.push_back(*prev(rank.end()) + 1);
            continue;
        }
        
        for(int i = 0; i < scores.size(); i++) {
            if(a >= scores[i]) {
                res.push_back(rank[i]);
                break;
            }
        }
    }
    return res;
}

Submission 2

• O(n + mlog(n))
• lower_bound
• lambda function

#include <bits/stdc++.h>

using namespace std;

vector<string> split_string(string);

// Complete the climbingLeaderboard function below.
vector<int> climbingLeaderboard(vector<int> scores, vector<int> alice) {
    vector<int> rank;
    rank.push_back(1);
    for(int i = 1, r = 1; i < scores.size(); ++i) {
        if(scores[i] == scores[i - 1]) {
            rank.push_back(r);
        } else {
            rank.push_back(++r);
        }
    }
    vector<int> res;
    for(auto a : alice) {
        if(a < *prev(scores.end())) {
            res.push_back(*prev(rank.end()) + 1);
            continue;
        }

        auto lb = lower_bound(scores.begin(), scores.end(), a, 
            [](const int m, const int& n) -> bool {
                return m > n;
            });
        res.push_back(rank[lb - scores.begin()]);

    }
    return res;
}

int main()
{
    ofstream fout(getenv("OUTPUT_PATH"));

    int scores_count;
    cin >> scores_count;
    cin.ignore(numeric_limits<streamsize>::max(), '\n');

    string scores_temp_temp;
    getline(cin, scores_temp_temp);

    vector<string> scores_temp = split_string(scores_temp_temp);

    vector<int> scores(scores_count);

    for (int i = 0; i < scores_count; i++) {
        int scores_item = stoi(scores_temp[i]);

        scores[i] = scores_item;
    }

    int alice_count;
    cin >> alice_count;
    cin.ignore(numeric_limits<streamsize>::max(), '\n');

    string alice_temp_temp;
    getline(cin, alice_temp_temp);

    vector<string> alice_temp = split_string(alice_temp_temp);

    vector<int> alice(alice_count);

    for (int i = 0; i < alice_count; i++) {
        int alice_item = stoi(alice_temp[i]);

        alice[i] = alice_item;
    }

    vector<int> result = climbingLeaderboard(scores, alice);

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

        if (i != result.size() - 1) {
            fout << "\n";
        }
    }

    fout << "\n";

    fout.close();

    return 0;
}

vector<string> split_string(string input_string) {
    string::iterator new_end = unique(input_string.begin(), input_string.end(), [] (const char &x, const char &y) {
        return x == y and x == ' ';
    });

    input_string.erase(new_end, input_string.end());

    while (input_string[input_string.length() - 1] == ' ') {
        input_string.pop_back();
    }

    vector<string> splits;
    char delimiter = ' ';

    size_t i = 0;
    size_t pos = input_string.find(delimiter);

    while (pos != string::npos) {
        splits.push_back(input_string.substr(i, pos - i));

        i = pos + 1;
        pos = input_string.find(delimiter, i);
    }

    splits.push_back(input_string.substr(i, min(pos, input_string.length()) - i + 1));

    return splits;
}