题目描述

blablabla

样例

blablabla

算法1

Java 代码

import java.io.*; 
import java.util.*;

public class Main{
    static int N = 100003;
    static int[] h = new int[N];
    static int[] e = new int[N];
    static int[] ne = new int[N];
    static int idx;

    static void insert(int x){
        // set Hash key make positive
        int k = (x % N + N) % N;
        e[idx] = x;
        ne[idx] = h[k];
        h[k] = idx++;
    }

    static boolean find(int x){
        int k = (x % N + N) % N;
        for(int i = h[k] ; i != -1 ; i = ne[i]){
            if(e[i] == x) return true;
        }
        return false;
    }

    public static void main(String[] args) throws Exception{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int n = Integer.valueOf(br.readLine());
        for(int i=0;i<N;i++){
            h[i]=-1;
        }
        while(n-- > 0){
            String[] s = br.readLine().split("\\s+");
            int x = Integer.valueOf(s[1]);
            if(s[0].equals("I")){
                insert(x);
            }else{
                if(find(x))    System.out.println("Yes");
                else    System.out.println("No");
            }
        }
    }
}