[C++][Implementation] Grading Students

https://www.hackerrank.com/challenges/grading/problem

 

#include <bits/stdc++.h>

using namespace std;

string ltrim(const string &);
string rtrim(const string &);

/*
 * Complete the 'gradingStudents' function below.
 *
 * The function is expected to return an INTEGER_ARRAY.
 * The function accepts INTEGER_ARRAY grades as parameter.
 */

vector<int> gradingStudents(vector<int> grades) {

  int sNum = grades.size();
  vector<int> roundedGrade(sNum);

  for (int i = 0; i < sNum; i++) {
    if (grades[i] < 38) {
      roundedGrade[i] = grades[i];
    }
    else {
        int re = grades[i] % 5;
        if (re > 2) {
            // when re == 4 or re == 3
            roundedGrade[i] = grades[i] + (5 - re);
        }
        else {
            roundedGrade[i] = grades[i];
        }
    }
  }
  
  return roundedGrade;
}

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

    string grades_count_temp;
    getline(cin, grades_count_temp);

    int grades_count = stoi(ltrim(rtrim(grades_count_temp)));

    vector<int> grades(grades_count);

    for (int i = 0; i < grades_count; i++) {
        string grades_item_temp;
        getline(cin, grades_item_temp);

        int grades_item = stoi(ltrim(rtrim(grades_item_temp)));

        grades[i] = grades_item;
    }

    vector<int> result = gradingStudents(grades);

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

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

    fout << "\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;
}