区间贪心

问题描述，给出N个开区间，选出尽可能多的开区间使其两两不相交，策略是选左端点尽可能大的点（或者右端点尽可能小的点）

#include<cstdio>
#include<algorithm>
using namespace std;
const int maxn = 110;
struct Inteval{
    int x, y;
}I[maxn];
bool cmp (Inteval a, Interval b){
    if(a.x != b.x) return a.x > b.x;
    else return a.y < b.y;
}
int main(){
    int n;
    while(scanf("%d",&n)!=0){
        for(int i = 0; i < n; i++){
            scanf("%d %d",&I[i].x, &I[i].y);
        }
        sort(I, I + n, cmp);
        int ans = 1, lastX = I[0].x;
        for(int i = 1; i < n; i++){
            if(I[i].y <= lastX){
                lastX = I[i].x;
                ans++;
            }
        }
        printf("%d\n",ans);
    }
    return 0;
}