zoukankan      html  css  js  c++  java
  • Codeforces 950 D A Leapfrog in the Array

    Discription

    Dima is a beginner programmer. During his working process, he regularly has to repeat the following operation again and again: to remove every second element from the array. One day he has been bored with easy solutions of this problem, and he has come up with the following extravagant algorithm.

    Let's consider that initially array contains n numbers from 1 to n and the number iis located in the cell with the index 2i - 1 (Indices are numbered starting from one) and other cells of the array are empty. Each step Dima selects a non-empty array cell with the maximum index and moves the number written in it to the nearest empty cell to the left of the selected one. The process continues until all n numbers will appear in the first n cells of the array. For example if n = 4, the array is changing as follows:

    You have to write a program that allows you to determine what number will be in the cell with index x (1 ≤ x ≤ n) after Dima's algorithm finishes.

    Input

    The first line contains two integers n and q (1 ≤ n ≤ 10181 ≤ q ≤ 200 000), the number of elements in the array and the number of queries for which it is needed to find the answer.

    Next q lines contain integers xi (1 ≤ xi ≤ n), the indices of cells for which it is necessary to output their content after Dima's algorithm finishes.

    Output

    For each of q queries output one integer number, the value that will appear in the corresponding array cell after Dima's algorithm finishes.

    Example

    Input
    4 3
    2
    3
    4
    Output
    3
    2
    4
    Input
    13 4
    10
    5
    4
    8
    Output
    13
    3
    8
    9

    Note

    The first example is shown in the picture.

    In the second example the final array is [1, 12, 2, 8, 3, 11, 4, 9, 5, 13, 6, 10, 7].

    找规律题。

    #include<bits/stdc++.h>
    #define ll long long
    using namespace std;
    ll N,pos;
    int Q,tp;
    
    inline void solve(){
        tp=1;
        ll base=0,lef=N;
        while(1){
            if(!((tp^pos)&1)){
                printf("%lld
    ",base+(pos+tp)/2);
                return;
            }
            if(tp){
                tp=(lef&1)?0:1;
                base+=(lef+1)>>1;
                lef>>=1,pos>>=1;
            }
            else{
                tp=(lef&1)?1:0;
                base+=lef>>1;
                lef=(lef+1)>>1;
                pos=(pos+1)>>1;
            }
        }
    }
    
    int main(){
        scanf("%lld%d",&N,&Q);
        while(Q--){
            scanf("%lld",&pos);
            solve();
        }
        return 0;
    }
    

      

  • 相关阅读:
    【Android-功能】Android应用增量更新
    【android-音视频】listview中播放音频,实现音频时长的倒计时,暂停,切换。
    Mysql中的DQL查询语句
    DDL、DML和DCL的理解
    WIN2000 XP 2003系统密码破解方法
    ASP.NET开发学习视频教程大全(共800集)
    VS2010中,无法嵌入互操作类型“……”,请改用适用的接口的解决方法
    正则表达式-RegExp-常用正则表达式
    20151216
    20151124-数据类型
  • 原文地址:https://www.cnblogs.com/JYYHH/p/8625683.html
Copyright © 2011-2022 走看看