제출 #725438

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
725438		groshi	Building Bridges (CEOI17_building)	C++17	100 / 100	75 ms	35148 KiB

building

#include<bits/stdc++.h>
#define int long long
typedef long double ld;
typedef long long ll;
using namespace std;
const int C = (int)5e4 + 5;
int dp[200000];
int w[200000];
int h[200000];
const int mxN = (int)1e5+10;
const int mxC = (int)1e6+10;
const int LINF = (int)1e12+10;

struct Line{
	int m, c;
	Line(){ m=c=LINF; }
	Line(int _m, int _c){ m = _m, c = _c;}
	int operator()(int x){ return m*x+c; }
} seg[2*mxC+10];

void addLine(Line a, int p=0, int l=1, int r=mxC){
	if(l==r){
		if(seg[p](l)>a(l)) seg[p]=a;
		return;
	}
	int mid = (l+r)>>1; int rp = p+2*(mid-l+1);
	if(a.m > seg[p].m) swap(a,seg[p]);
	if(a(mid) < seg[p](mid))
		swap(a,seg[p]), addLine(a,p+1,l,mid);
	else addLine(a,rp,mid+1,r);
}

int query(int x, int p=0, int l=1, int r=mxC){
	if(l==r) return seg[p](x);
	int mid = (l+r)>>1; int rp = p+2*(mid-l+1);
	if(x<=mid) return min(query(x,p+1,l,mid),seg[p](x));
	return min(query(x,rp,mid+1,r),seg[p](x));
}

int32_t main()
{
    cin.tie(0);
    cout.tie(0);
    ios_base::sync_with_stdio(0);
    int n;
    cin>>n;
    for(int i=1;i<=n;i++)
        cin>>h[i];
    for(int i=1;i<=n;i++)
        cin>>w[i];
    for(int i=2;i<=n;i++)
        w[i]+=w[i-1];
    addLine({-2*h[1],h[1]*h[1]-w[1]});
    for(int i=2;i<=n;i++)
    {
        dp[i]=query(h[i])+h[i]*h[i]+w[i-1];
        addLine({-2*h[i],h[i]*h[i]-w[i]+dp[i]});
    }
    cout<<dp[n];
    return 0;
}

• Subtask 1: 30 / 30
• Subtask 2: 30 / 30
• Subtask 3: 40 / 40