1 //只需要按照结束时间排序贪心即可
2 #include <iostream>
3 #include <algorithm>
4 using namespace std;
5 typedef struct
6 {
7 int x,y;
8 }P;
9 P p[10005];
10 bool cmp(P a,P b)
11 {
12 if(a.y < b.y) return true;
13 else if(a.y == b.y && a.x > b.x) return true;
14 return false;
15 }
16 int main()
17 {
18 int t,n;
19 cin >> t;
20 while(t--)
21 {
22 cin >> n;
23 for(int i=0; i<n; ++i)
24 cin >> p[i].x >> p[i].y;
25 sort(p,p+n,cmp);
26 int ans = 1,temp = p[0].y;
27 for(int i=1; i<n; ++i)
28 if(p[i].x > temp)
29 {
30 ++ans;
31 temp = p[i].y;
32 }
33 cout << ans << endl;
34 }
35 return 0;
36 }
1 //最优程序
2 #include<stdio.h>
3 #include <vector>
4 #include<algorithm>
5 #include<math.h>
6 using namespace std;
7
8 struct activ
9 {
10 int begin;
11 int end;
12 };
13 bool cmp( activ a,activ b)
14 {
15 return a.end<b.end;
16 }
17 int main()
18 {
19 //freopen("1.txt","r",stdin);
20 int n;
21 scanf("%d",&n);
22 while (n--)
23 {
24 int m;
25 scanf("%d",&m);
26 vector<activ> vec;
27 for(int i=0;i<m;i++)
28 {
29 activ a;
30 scanf("%d%d",&a.begin,&a.end);
31 vec.push_back(a);
32 }
33
34 sort(vec.begin(),vec.end(),cmp);
35 int count=vec.size();
36 int k=0;
37 for (int i=1;i<vec.size();i++)
38 {
39 if(vec[i].begin <= vec[k].end)
40 count--;
41 else k=i;
42 }
43 printf("%d\n",count);
44 }
45
46 return 0;
47 }
