#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <utility>
#include <stack>
#include <vector>
#include <queue>
#include <deque>
#include <set>
#include <map>

using namespace std;

bool isLeap(int year) {
    return (year%4 == 0) && (!(year%100 == 0) || (year % 400 == 0));
}

const int monthLengths[] = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

#define INV {cout << "invalid" << endl; continue; }

int main(void){
    string s;
    while (cin >> s) {
	if (s == "end") break;
	if (s.length() != 10 && s.length() != 11) INV
	if (s[6] != '/') INV
	if (!isdigit(s[0])) INV
	if (!isdigit(s[1])) INV
	if (!isdigit(s[2])) INV
	if (!isdigit(s[3])) INV
	if (!isdigit(s[4])) INV
	if (!isdigit(s[5])) INV
	if (!isdigit(s[7])) INV
	if (!isdigit(s[8])) INV
	if (!isdigit(s[9])) INV
	if (s.length() == 11 && !isdigit(s[10])) INV
	
	bool isBoy = false;
	int year = (s[0]-'0')*10 + s[1]-'0';
	int month = (s[2]-'0')*10 + s[3]-'0';
	int day = (s[4]-'0')*10 + s[5]-'0';
	
	isBoy = (month < 50);
	if (month > 50) {
	    month -= 50;
	}
	
	// mesic je spravne
	// den taky
	
	if (year >=0 && year <= 9) {
	    if (s.length() != 11) INV
	    year += 2000;
	}
	else if (year >=10 && year <= 19) INV
	else if (year >=20 && year <= 53) {
	    if (s.length() != 10) INV
	    year += 1900;
	}
	else if (year >=53 && year <= 99) {
	    if (s.length() != 11) INV
	    year += 1900;
	}
	else {
	    cout << "BLBE!" << endl;
	}
	
	// v year je 4ciferny rok
	if (month <= 0 || month > 12) INV
	if (day <= 0 || day > monthLengths[month-1]) INV
	if (!isLeap(year) && month == 2 && day == 29) INV
	
	// rozsahy dobre
	
	if (!(year >= 1920 && year <= 1953)) {
	  // delitelnost 11
	  int sum = 0;
	  int parity = 1;
	  for (unsigned i=0; i<s.length(); i++) {
	      if (i == 6) continue;
	      sum += (parity * (s[i]-'0'));
	      parity *= -1;
	  }
	  if (sum%11 != 0) INV
	}
	if (isBoy) cout << "boy" << endl;
	else cout << "girl" << endl;
    }
  
    return 0;
}