oj.uz

Submission #291162

# Submission time Handle Problem Language Result Execution time Memory
291162 2020-09-04T19:45:55 Z Bench0310 Building Bridges (CEOI17_building) C++17
100 / 100
 78 ms 9976 KB 
#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef long double ld;

const ll inf=(1ll<<60);

struct line
{
    ll k,n;
    mutable ll r;
    line(ll a,ll b,ll c){k=a;n=b;r=c;}
};

bool operator<(const line &a,const line &b){return a.k>b.k;}
bool operator<(const line &a,const ll &b){return a.r<b;}

ld intersect(line a,line b){return (((ld)b.n-a.n)/(a.k-b.k));}

struct cht
{
    set<line,less<>> s;
    void upd(set<line>::iterator it,ll nr){it->r=nr;}
    void add(ll k,ll n)
    {
        line now(k,n,0);
        auto it=s.lower_bound(now);
        if(it!=s.end()&&it->k==k)
        {
            if(it->n>n) it=s.erase(it);
            else return;
        }
        if(it!=s.end()&&it!=s.begin()&&intersect(*prev(it),now)>intersect(now,*it)) return;
        s.insert(now);
        while(it!=s.end()&&next(it)!=s.end()&&intersect(now,*it)>intersect(*it,*next(it))) it=s.erase(it);
        it--;
        while(it!=s.begin()&&prev(it)!=s.begin()&&intersect(now,*prev(it))<intersect(*prev(it),*prev(prev(it)))) s.erase(prev(it));
        if(it!=s.begin()) upd(prev(it),floor(intersect(*prev(it),*it)));
        if(next(it)!=s.end()) upd(it,floor(intersect(*it,*next(it))));
        else upd(it,inf);
    }
    ll query(ll a)
    {
        line best=*s.lower_bound(a);
        return (best.k*a+best.n);
    }
};

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    int n;
    cin >> n;
    vector<ll> h(n+1,0);
    for(int i=1;i<=n;i++) cin >> h[i];
    vector<ll> w(n+1,0);
    for(int i=1;i<=n;i++) cin >> w[i];
    vector<ll> sum(n+1,0);
    for(int i=1;i<=n;i++) sum[i]=sum[i-1]+w[i];
    cht c;
    c.add(-2*h[1],h[1]*h[1]-w[1]);
    for(int i=2;i<=n;i++)
    {
        ll dp=h[i]*h[i]+sum[i-1]+c.query(h[i]);
        c.add(-2*h[i],dp+h[i]*h[i]-sum[i]);
        if(i==n) cout << dp << "\n";
    }
    return 0;
}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 0 ms 384 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 77 ms 3820 KB Output is correct
2 Correct 78 ms 3840 KB Output is correct
3 Correct 70 ms 3832 KB Output is correct
4 Correct 66 ms 3712 KB Output is correct
5 Correct 63 ms 4984 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 0 ms 384 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 77 ms 3820 KB Output is correct
7 Correct 78 ms 3840 KB Output is correct
8 Correct 70 ms 3832 KB Output is correct
9 Correct 66 ms 3712 KB Output is correct
10 Correct 63 ms 4984 KB Output is correct
11 Correct 60 ms 3960 KB Output is correct
12 Correct 72 ms 3832 KB Output is correct
13 Correct 43 ms 3840 KB Output is correct
14 Correct 66 ms 3960 KB Output is correct
15 Correct 76 ms 9976 KB Output is correct
16 Correct 59 ms 4864 KB Output is correct
17 Correct 21 ms 3840 KB Output is correct
18 Correct 20 ms 3840 KB Output is correct