dairy

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

void dump(const vector<vector<string>>& data) {
    int day;
    cin >> day;
    if (data[day - 1].size() == 0) {
        cout << data[day - 1].size() << '\n';
    }
    else {
        cout << data[day - 1].size() << ' ';
        for (const auto& s : data[day - 1]) {
            cout << s << ' ';
        }
        cout << endl;
    }
}
/*
We added new string for section vector with index [day-1]
*/
void add(vector<vector<string>>& data) {
    int day;
    string work;
    cin >> day >> work;
    data[day - 1].push_back(work);
}
void next(vector<vector<string>>& data, const vector<int>& month, int& mi) {
    if (mi == 11) {//If year is ended, we define new month
        mi = 0;
    }
    else if (mi != 11){

        if (month[mi+1] > month[mi]) {//if new month has a bigger index, we only using resize
            data.resize(month[mi+1]);
            ++mi;
        }

        else if (month[mi+1] < month[mi]) {
            vector<string> temp;
            int diff = month[mi] - month[mi+1];//search, a lot of many indexating vectors are diffirence
            for (int i = diff; i > 0; --i) {
                //In this code we write a data on vector temp
                for (string& s : data[month[mi] - i]) {
                    data[month[mi+1]-1].push_back(s);
                }
            }
            data.resize(month[mi+1]);
            ++mi;
        }
        else if (month[mi + 1] == month[mi]) {
            ++mi;
        }
    }
}
int main() {
    /*****************
    Declaration using variables on upper function
    *********************************/
    vector<vector<string>> data(31);
    int mi = 0;
    const vector<int> month = { 31,28,31,30,31,30,31,31,30,31,30,31 };
    /*****************************
    Declarate template variables for select work code
    *********************/
    int n;
    string sel;
    cin >> n;
    /*************************************************/
    for (int i = 0; i < n; ++i) {
        cin >> sel;
        if (sel == "ADD") {
            add(data);
        }
        else if (sel == "DUMP") {
            dump(data);
        }
        else if (sel == "NEXT") {
            next(data, month, mi);
        }
    }
}