BZOJ【1588】营业额统计 set

版权声明：转载记得声明噢！ https://blog.csdn.net/Richard__Luan/article/details/82192694

平生第一次写纯stl题。。这里用到lower-bound，就是查找第一个大于等于这个数的数。

#include<cstdio>
#include<iostream>
#include<set>
#include<cstdlib>
using namespace std;
set<int> s;
int n;
int ans;
int main()
{
	scanf("%d",&n);
	for(int i=1;i<=n;i++)
	{
		int x;
		scanf("%d",&x);
		if(i==1)
		{
			ans+=x;
			s.insert(x);
			continue;
		}
		set<int> ::iterator ii=s.lower_bound(x);
		int minn=1000000000;
		int zzz=abs(x - *ii);
		minn=min(minn,zzz);
		if(ii!=s.begin())
		{
			ii--; 
			int zzz=abs(x - *ii);
			minn=min(minn,zzz);
		}
		ans+=minn;
		s.insert(x);
	}
	printf("%d",ans);
	return 0;
}