贪心 00 1

Problem B

Time Limit : 2000/1000ms (Java/Other)   Memory Limit : 65536/32768K (Java/Other)

Total Submission(s) : 111   Accepted Submission(s) : 36

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

 这个题 一般提 一个标记数组 然后按照后面的排列 然后全局ok然后排列前一个 

很正常的贪心

#include<iostream>
#include<string.h>
#include<set>
#include<stdio.h>
#include<vector>
#include<algorithm>
#include<numeric>
#include<math.h>
#include<string.h>
#include<sstream>
#include<stdio.h>
#include<string>
#include<cstdlib>
#include<algorithm>
#include<iostream>
#include<map>
#include<queue>
#include<string>
using namespace std;
struct hh
{
    int a;
    int b;
};
bool cmp(const hh &s,const hh &w)
{

    if(s.a<w.a) return true;
    else if(s.a==w.a)return s.b<w.b;
    return false;
}
int main()
{
    int n;
    cin>>n;
    int i;
    hh  a[10000];
    int b[10000];
    int max;
    int t;
    for(i=1;i<=n;i++)
    {
        int w;
        cin>>w;
        int j;
        for(j=1;j<=w;j++)
        {
            cin>>a[j].a;
            cin>>a[j].b;
        }
        sort(a+1,a+w+1,cmp);
        memset(b,0,sizeof(b));
        int l;
        int sum;
        sum=0;
        int i,paopao ,s,ss,sss,ff;
        for(j=1;j<=w;j++)
        {
            if(b[j]==1)
            continue;
            b[j]=1                                                                                                      ;
            sum++;
            paopao=a[j].b;
                for(ss=j+1;ss<=w;ss++)
            {
                if(paopao<=a[ss].b&&b[ss]==0)
                { paopao=a[ss].b;
                 b[ss]=1;
                }
            }
            sss=0;
            for(ff=1;ff<=w;ff++)
            if(b[ff]==1)
            sss++;
            if(sss==w)
            break;
        }
        cout<<sum<<endl;
    }
    return 0;
}