Shuffle Cards 解题报告（STL模板 rope）

时间限制：C/C++ 1秒，其他语言2秒
空间限制：C/C++ 262144K，其他语言524288K
Special Judge, 64bit IO Format: %lld

题目描述

Eddy likes to play cards game since there are always lots of randomness in the game. For most of the cards game, the very first step in the game is shuffling the cards. And, mostly the randomness in the game is from this step. However, Eddy doubts that if the shuffling is not done well, the order of the cards is predictable!

To prove that, Eddy wants to shuffle cards and tries to predict the final order of the cards. Actually, Eddy knows only one way to shuffle cards that is taking some middle consecutive cards and put them on the top of rest. When shuffling cards, Eddy just keeps repeating this procedure. After several rounds, Eddy has lost the track of the order of cards and believes that the assumption he made is wrong. As Eddy's friend, you are watching him doing such foolish thing and easily memorizes all the moves he done. Now, you are going to tell Eddy the final order of cards as a magic to surprise him.

Eddy has showed you at first that the cards are number from 1 to N from top to bottom.

For example, there are 5 cards and Eddy has done 1 shuffling. He takes out 2-nd card from top to 4-th card from top(indexed from 1) and put them on the top of rest cards. Then, the final order of cards from top will be [2,3,4,1,5].

输入描述:

The first line contains two space-separated integer N, M indicating the number of cards and the number of shuffling Eddy has done.
Each of following M lines contains two space-separated integer pi, si indicating that Eddy takes pi-th card from top to (pi+si-1)-th card from top(indexed from 1) and put them on the top of rest cards.


1 ≤ N, M ≤ 105
1 ≤ pi ≤ N
1 ≤ si ≤ N-pi+1

输出描述:

Output one line contains N space-separated integers indicating the final order of the cards from top to bottom.

示例1

输入

5 1
2 3

输出

2 3 4 1 5

示例2

输入

5 2
2 3
2 3

输出

3 4 1 2 5

示例3

输入

5 3
2 3
1 4
2 4

输出

3 4 1 5 2

题解

题意：
这个题目的意思是给你n个数（1,2,3...n），m个操作，然后输入m行，每行有两个数pi，si，每个操作代表将这n个数的下标在pi到（pi+si-1）的数放到最前面。比如第二个样例，n=5，代表[1，2，3，4，5]，m代表有两个操作，第一行输入2，3表示将[2，3，4]挪到最前面，这时数列变为[2，3，4，1，5]。然后又输入2，3，表示将[3，4，1]放到最前面，这时数列变为[3，4，1，2，5]。

解析：
用到STL模板库中的rope

AC code

#include <bits/stdc++.h>
#include <ext/rope>
#define ll long long
#define PI 3.1415926535
using namespace std;
using namespace __gnu_cxx;
const int NUM = 1e3 + 10;
const int INF = 2147483647;
const int mod = 1000000009;

int main()
{
    int n,m;
    cin>>n>>m;
    rope<int> q;
    for(int i=1;i<=n;i++){
        q.push_back(i);
    }
    int s,p;
    for(int i=0;i<m;i++){
        cin>>s>>p;
        q=q.substr(s-1,p)+q.substr(0,s-1)+q.substr(s+p-1,n-s-p+1);
    }
    for(int i=0;i<n;i++){
        cout<<q[i]<<" ";
    }
    cout<<endl;
    return 0;
}