problem
solution
codes
#include<iostream>
#include<algorithm>
using namespace std;
const int maxn = 110;
int a[maxn], b[maxn], c[maxn];
bool cmp(int x, int y){
return b[x]==b[y] ? a[x]<a[y] : b[x]<b[y];
}
int main(){
int n; cin>>n;
for(int i = 1; i <= n; i++){
int x, y; cin>>x>>y; //输入有坑,可能先大再小
a[i]=min(x,y); b[i]=max(x,y); c[i]=i;
}
sort(c+1,c+n+1,cmp);
//for(int i = 1; i <= n; i++)cout<<a[c[i]]<<" "<<b[c[i]]<<"
";
int t = -999, ans = 0;
for(int i = 1; i <= n; i++){
if(t <= a[c[i]]){
t = b[c[i]]; ans++;
}
}
cout<<ans<<"
";
return 0;
}