LarrysArray.cpp

#include <bits/stdc++.h>

using namespace std;

string ltrim(const string &);
string rtrim(const string &);
vector<string> split(const string &);

/*
 * Complete the 'larrysArray' function below.
 *
 * The function is expected to return a STRING.
 * The function accepts INTEGER_ARRAY A as parameter.
 */

string larrysArray(vector<int> A) {
    int n = A.size();
    int inversions = 0;

    // Count inversions in the array
    for (int i = 0; i < n; i++) {
        for (int j = i + 1; j < n; j++) {
            if (A[i] > A[j]) {
                inversions++;
            }
        }
    }

    // Check if the number of inversions is even
    if (inversions % 2 == 0) {
        return "YES";
    } else {
        return "NO";
    }
}

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

    string t_temp;
    getline(cin, t_temp);

    int t = stoi(ltrim(rtrim(t_temp)));

    for (int t_itr = 0; t_itr < t; t_itr++) {
        string n_temp;
        getline(cin, n_temp);

        int n = stoi(ltrim(rtrim(n_temp)));

        string A_temp_temp;
        getline(cin, A_temp_temp);

        vector<string> A_temp = split(rtrim(A_temp_temp));

        vector<int> A(n);

        for (int i = 0; i < n; i++) {
            int A_item = stoi(A_temp[i]);

            A[i] = A_item;
        }

        string result = larrysArray(A);

        fout << result << "\n";
    }

    fout.close();

    return 0;
}

string ltrim(const string &str) {
    string s(str);

    s.erase(
            s.begin(),
            find_if(s.begin(), s.end(), not1(ptr_fun<int, int>(isspace)))
    );

    return s;
}

string rtrim(const string &str) {
    string s(str);

    s.erase(
            find_if(s.rbegin(), s.rend(), not1(ptr_fun<int, int>(isspace))).base(),
            s.end()
    );

    return s;
}

vector<string> split(const string &str) {
    vector<string> tokens;

    string::size_type start = 0;
    string::size_type end = 0;

    while ((end = str.find(" ", start)) != string::npos) {
        tokens.push_back(str.substr(start, end - start));

        start = end + 1;
    }

    tokens.push_back(str.substr(start));

    return tokens;
}