xtu read problem training 4 A

Moving Tables

Time Limit: 2000ms

Memory Limit: 65536KB

This problem will be judged on ZJU. Original ID: 1029
64-bit integer IO format: %lld      Java class name: Main

 

The famous ACM (Advanced Computer Maker) Company has rented a floor of a building whose shape is in the following figure.

The floor has 200 rooms each on the north side and south side along the corridor. Recently the Company made a plan to reform its system. The reform includes moving a lot of tables between rooms. Because the corridor is narrow and all the tables are big, only one table can pass through the corridor. Some plan is needed to make the moving efficient. The manager figured out the following plan: Moving a table from a room to another room can be done within 10 minutes. When moving a table from room i to room j, the part of the corridor between the front of room i and the front of room j is used. So, during each 10 minutes, several moving between two rooms not sharing the same part of the corridor will be done simultaneously. To make it clear the manager illustrated the possible cases and impossible cases of simultaneous moving.

For each room, at most one table will be either moved in or moved out. Now, the manager seeks out a method to minimize the time to move all the tables. Your job is to write a program to solve the manager��s problem. 


Input 

The input consists of T test cases. The number of test cases ) (T is given in the first line of the input. Each test case begins with a line containing an integer N , 1<=N<=200 , that represents the number of tables to move. Each of the following N lines contains two positive integers s and t, representing that a table is to move from room number s to room number t (each room number appears at most once in the N lines). From the N+3-rd line, the remaining test cases are listed in the same manner as above. 

Output 

The output should contain the minimum time in minutes to complete the moving, one per line. 


Sample Input 

3 
4 
10 20 
30 40 
50 60 
70 80 
2 
1 3 
2 200 
3 
10 100 
20 80 
30 50

Output for the Sample Input

10 
20 
30

 

Source

Asia 2001, Taejon (South Korea)

 

解题：比较有意思的题目，求交点的问题。搬桌子！！！！！！！第2k个房间与第2k-1个房间是正对着的，他们共用门前的走廊的部分。所以假设他们共用的走廊为y .  y = (2k+1)/2

 

或者 y = (2k-1+1)/2

 

搬桌子，搬桌子的最长时间是由冲突最多的一次搬运决定的，要是搬桌子的时间尽可能的短，那么需要使最长的那部分时间 尽可能的短！所以求出冲突次数最多的走廊。次数*10就是结果

 

 

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <climits>
#include <vector>
#include <queue>
#include <cstdlib>
#include <string>
#include <set>
#include <stack>
#define LL long long
#define INF 0x3f3f3f3f
using namespace std;
int a[201];
int main() {
    int k,s,t,j,mx,n;
    scanf("%d",&k);
    while(k--) {
        mx = 0;
        memset(a,0,sizeof(a));
        scanf("%d",&n);
        while(n--) {
            scanf("%d%d",&s,&t);
            if(s > t) swap(s,t);
            s = (s+1)/2;
            t = (t+1)/2;
            for(j = s; j <= t; j++) {
                ++a[j]; if(a[j] > mx) mx = a[j];
            }
        }
        printf("%d
",mx*10);
    }
    return 0;
}