Submission #1040381

#	Time	Username	Problem	Language	Result	Execution time	Memory
1040381		vjudge1	Divide and conquer (IZhO14_divide)	C++17	100 / 100	21 ms	8292 KiB

divide

#include<bits/stdc++.h>
using namespace std;
long long n,x[100005],g[100005],d[100005],cv[100005],f[100005],ans=0;
int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);cout.tie(0);
//	freopen(".inp","r",stdin);
//	freopen(".out","w",stdout);
	cin>>n;
	for(int i=1;i<=n;i++)
	{
		cin>>x[i]>>g[i]>>d[i];
		cv[i]=cv[i-1]+g[i];
		f[i]=f[i-1]+d[i];
	}
	vector<long long> v,u;
	v.push_back(f[0]-x[1]);
	u.push_back(1);
	ans=g[1];
	for(int i=2;i<=n;i++)
	{
		long long vl=f[i-1]-x[i];
		if(vl<v[v.size()-1]) {v.push_back(vl);u.push_back(i);}
		long long k=f[i]-x[i];
		long long l=0,r=v.size()-1,vt=-1;
		while(l<=r)
		{
			long long mid=(l+r)/2;
			if(v[mid]<=k)
			{
				r=mid-1;
				vt=mid;
			}
			else l=mid+1;
		}
//		cout<<k<<' '<<vt<<endl;
		if(vt==-1) continue;
		long long h=u[vt];
//		cout<<k<<' '<<h<<' '<<i<<endl;
		ans=max(ans,cv[i]-cv[h-1]);
	}
	cout<<ans;
	return 0;
}

• Subtask 1: 17 / 17
• Subtask 2: 31 / 31
• Subtask 3: 52 / 52