Grouping with map of vectors

Lab C++ Intermediate 20 points

Read lines department name and print each department (sorted) with its names in input order.

Input

n, then n lines.

Output

One line per department: dept: a, b

Example

Input

5
sales zoe
it amy
sales bob
hr cy
it dan

Output

hr: cy
it: amy, dan
sales: zoe, bob

Sample input available Sample output available

Editor

C++

Hints

groups[dept] creates an empty vector the first time.

Solution explanation

A map from key to vector is the standard grouping structure.

Show solution

#include <iostream>
#include <map>
#include <string>
#include <vector>
using namespace std;

int main() {
    int n;
    cin >> n;
    map<string, vector<string>> groups;
    for (int i = 0; i < n; i++) {
        string dept, name;
        cin >> dept >> name;
        groups[dept].push_back(name);
    }
    for (const auto &[dept, names] : groups) {
        cout << dept << ": ";
        for (size_t i = 0; i < names.size(); i++) cout << names[i] << (i + 1 < names.size() ? ", " : "\n");
    }
    return 0;
}

Output

Answer