Wooden Sticks
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 11244 Accepted Submission(s): 4627
Problem Description There is a pile of n wooden sticks. The length and weight of each stick are known in advance. The sticks are to be processed by a woodworking machine in one by one fashion. It needs some time, called setup time, for the machine to prepare processing a stick. The setup times are associated with cleaning operations and changing tools and shapes in the machine. The setup times of the woodworking machine are given as follows:
(a) The setup time for the first wooden stick is 1 minute.
(b) Right after processing a stick of length l and weight w , the machine will need no setup time for a stick of length l' and weight w' if l<=l' and w<=w'. Otherwise, it will need 1 minute for setup.
You are to find the minimum setup time to process a given pile of n wooden sticks. For example, if you have five sticks whose pairs of length and weight are (4,9), (5,2), (2,1), (3,5), and (1,4), then the minimum setup time should be 2 minutes since there is a sequence of pairs (1,4), (3,5), (4,9), (2,1), (5,2).
Input The input consists of T test cases. The number of test cases (T) is given in the first line of the input file. Each test case consists of two lines: The first line has an integer n , 1<=n<=5000, that represents the number of wooden sticks in the test case, and the second line contains n 2 positive integers l1, w1, l2, w2, ..., ln, wn, each of magnitude at most 10000 , where li and wi are the length and weight of the i th wooden stick, respectively. The 2n integers are delimited by one or more spaces.
Output The output should contain the minimum setup time in minutes, one per line.
Sample Input
3
5
4 9 5 2 2 1 3 5 1 4
3
2 2 1 1 2 2
3
1 3 2 2 3 1
Sample Output
2
1
3
题意是第一个3是3组数据， 然后一个5是5根棍子， 然后逐一输入其的长度和重量。。题目是问怎么做这些棍子用时最少，在做棍子时，若后一根棍子，长度和重量都大于前
一根，则不用加时间。。
想法。。
拿第一组数据来说。。
首先按长度以小到大排序：（1,4），（2，1），（3， 5）， （4， 9），（5,2）；
我们发现（2， 1）的重量太小， 而（5， 2）的长度太长。这样排结果为3；
其实这时，我们只要把不满足的先标记起来。。
则（1,4），（3,5），（4,9） ―――― （2,1）， （5,2）
但我们这么排， 也就是题目给出的顺序，结果就为2；也就是最优。
#include
#include
#include
#include
#include
#include
#include
#include
using namespace std; #define M 100500 struct node { int lenth; int weight; int k; } Q[M]; bool cmp ( node a, node b ) { if(a.lenth==b.lenth) return a.weight
=t &&Q[j].k==1 ) { ans++; Q[j].k=0; t = Q[j].weight; } } printf("%d\n", n-ans); } return 0; }