1 #include<cstdio> 2 #include<algorithm> 3 #include<cstring> 4 using namespace std; 5 struct node 6 { 7     int st; 8     int ed; 9 };10 node a[110];11 int n,ans;12 bool cmp(node x,node y)13 {14     if (x.ed==y.ed) return x.st<y.st;15     return x.ed<y.ed;16 }17 int main()18 {19     scanf("%d",&n);20     while (n!=0)21     {22         memset(a,0,sizeof(a));23         for (int i=1;i<=n;i++) scanf("%d%d",&a[i].st,&a[i].ed);24         sort(a+1,a+n+1,cmp);25         //for (int i=1;i<=n;i++) printf("%d %d\n",i,a[i].ed);26         ans=0;27         int last=0;28         for (int i=1;i<=n;i++)29             if (a[i].st>=last)30             {31                 ans++;32                 last=a[i].ed;33             }34         printf("%d\n",ans);35         scanf("%d",&n);36     }37     return 0;38 }