Submission #334868

#	Time	Username	Problem	Language	Result	Execution time	Memory
334868		Gurban	Bigger segments (IZhO19_segments)	C++17	100 / 100	184 ms	34668 KiB

segments

#include <bits/stdc++.h>
using namespace std;

using ll = long long;

const int maxn=5e5+5;
int n,a[maxn];
ll p[maxn],T[4*maxn];
pair<int,ll>dp[maxn];

void upd(int pos,ll val,int l,int r,int nd){
	if(l == r){T[nd]=val;return;}
	if(pos <= (l+r)/2) upd(pos,val,l,(l+r)/2,nd*2);
	else upd(pos,val,(l+r)/2+1,r,nd*2+1);
	T[nd] = min(T[nd*2],T[nd*2+1]);
}

int tap(ll val,int l,int r,int nd){
	if(l==r) return l;
	if(T[nd*2+1] <= val) return tap(val,(l+r)/2+1,r,nd*2+1);
	return tap(val,l,(l+r)/2,nd*2);
}

int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);

	cin >> n;
	for(int i = 1;i <= 4*n;i++) T[i] = 1e18;
	for(int i = 1;i <= n;i++) cin >> a[i],p[i]=p[i-1]+a[i];
	dp[1] = {1,a[1]};
	upd(1,2*a[1],1,n,1);
	for(int i = 2;i <= n;i++){
		if(T[1] <= p[i]){
			int pos = tap(p[i],1,n,1);
			dp[i] = {dp[pos].first+1,p[i]-p[pos]};
		}
		else dp[i] = {dp[i-1].first,dp[i-1].second+a[i]};
		upd(i,dp[i].second+p[i],1,n,1);
	}
	// for(int i = 1;i <= n;i++) cout<<dp[i].first<<' ';
	cout<<dp[n].first;
}

• Subtask 1: 13 / 13
• Subtask 2: 14 / 14
• Subtask 3: 10 / 10
• Subtask 4: 36 / 36
• Subtask 5: 27 / 27