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

struct Time
{
    int hour;
    int minute;
    Time(){}
    Time(int hour,int minute)
    {
        this->hour=hour;
        this->minute=minute;
    }
    string to_string()
    {
        stringstream ss;
        if(hour<10)
            ss<<"0";
        ss<<hour<<":";
        if(minute<10)
            ss<<"0";
        ss<<minute;
        return ss.str();
    }

    // 重写操作符
    bool operator>=(const Time& b)
    {
        if(this->hour>b.hour)
            return true;
        else if(this->hour==b.hour)
            if(this->minute>=b.minute)
                    return true;
        return false;
    }
};

struct appUse
{
    string name;
    int priority;
    Time startTime;
    Time endTime;
    bool isInitialized=false;
    appUse(){}
    appUse(string name,int priority,Time startTime,Time endTime)
    {
        this->name=name;
        this->priority=priority;
        this->startTime=startTime;
        this->endTime=endTime;
        this->isInitialized=true;
    }
};

int strToInt(string input)
{
    stringstream ss;
    int n;
    ss<<input;
    ss>>n;
    return n;
}
Time strToTime(string input)
{
    stringstream ss;
    ss<<input;
    vector<string> out;
    string store;
    while(getline(ss,store,':'))
        out.push_back(store); 
    int hour=strToInt(out[0]),minute=strToInt(out[1]);
    return Time(hour,minute);
}
string judgeAvailableApp(vector<appUse> apps,Time inputTime)
{
    int priority=0;
    string outAppName="NA";
    appUse outApp;
    for(auto app:apps)
    {
        // 判断因为有时间重合而覆盖掉的情况
        if(outApp.isInitialized)
        {
            // 有重合
            if(!(outApp.startTime>=app.endTime||app.startTime>=outApp.endTime))
                // 有重合且outApp优先级小，则outApp被删除
                if(outApp.priority<app.priority)
                {
                    outAppName="NA";
                    outApp.isInitialized=false;
                }
        }
        if(inputTime>=app.startTime&&app.endTime>=inputTime&&app.priority>priority)
        {
            priority=app.priority;
            outAppName=app.name;
            outApp=app;
        }
    }
    return outAppName;
}
int main(int argc, char *argv[])
{
    vector<appUse> apps;
   int appAmount;
   cin>>appAmount;
   for(int i=0;i<appAmount;i++)
   {
        string appName,beginTime,endTime;
        int priority;
        cin>>appName>>priority>>beginTime>>endTime;
        appUse app(appName,priority,strToTime(beginTime),strToTime(endTime));
        apps.push_back(app);
   }
   string input;
   cin>>input;
   Time inputTime=strToTime(input);
   cout<<judgeAvailableApp(apps,inputTime);
}