Moving Tables
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 24833 Accepted Submission(s):
8217
Problem Description
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.
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
Sample Output
10
20
30
Source
Recommend
一道贪心题，要注意看图中的房间分布位置1-2,3-4可以同时搬，1-3,4-6却不可以同时搬。
题意：在一个长走廊里搬桌子，走廊的两侧都是房间，把桌子从一个房间搬到另外一个房间，走廊的宽度只能允许一个桌子通过，每次搬桌子需要10分钟（每一次允许再不交叉的走廊中同时搬桌子），问最少多长时间搬完。
附上代码：
1 #include <iostream> 2 #include <cstdio> 3 #include <cstring> 4 using namespace std; 5 int main() 6 { 7 int n,m,a,b,i,t,c[205],max,j; 8 scanf("%d",&n); 9 while(n--) 10 { 11 scanf("%d",&m); 12 memset(c,0,sizeof(c)); 13 for(i=1; i<=m; i++) 14 { 15 scanf("%d %d",&a,&b); 16 a=(a-1)/2; //将其转换为走廊，如1,2，算出来都是0，则为0走廊；3,4，算出来都是1，则为1走廊，等等。。 17 b=(b-1)/2; 18 if(a>b) 19 { 20 t=a; 21 a=b; 22 b=t; 23 } 24 for(j=a; j<=b; j++) //每次搬桌子，这些走廊都使用了一次 25 c[j]++; 26 } 27 max=0; 28 for(i=1; i<=200; i++) 29 if(max<c[i]) //找到使用次数最多的走廊，则为最少搬桌子次数 30 max=c[i]; 31 printf("%d ",max*10); 32 } 33 return 0; 34 }