C++ :

#include <bits/stdc++.h>
using namespace std;

int main(){
	int n,b,s,g,c = 0;
	cin>>n;
	
	for(int i = 1;i <= n;i++){
		b = i / 100;
		s = i / 10 % 10;
		g = i % 10;
		
		if(b==6 || s==6 || g==6){
			c++;
		}
	}
	
	if(c % 2 == 0){
		cout<<"playground";
	}else{
		cout<<"library";
	}
	return 0;
}

Java :

import java.util.Scanner;
public class Main{
public static void main (String[] args){
	Scanner sc = new Scanner(System.in);
	
	int n = sc.nextInt();
	int t = 0;
	if(n >= 10 && n <= 1000) {
	for(int i = 1; i<= n; i++) {
		if(i % 10 == 6 || i / 10 % 10 ==6 || i / 100 == 6) {
			t++;
			
		}
		
		}
		
	if(t++ % 2 ==0) {
	System.out.println("playground");
}else {
	System.out.println("library");
}
	
		
	}
	
	}
	}

Python :

#接收输入
n = int(input())
#初始化总数c
c = 0
#循环遍历1~n
for i in range(1, n + 1):
    #把i转换为字符串
    a = str(i)
    #把6转换为字符串
    b = '6'
    #如果6在a中，则c自加1
    if b in a:
        c += 1
#如果总数是奇数，则打印输出“图书馆”，否则去“游乐场”
if c % 2 != 0:
    print('library')
else:
    print('playground')