제출 #939322

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
939322		Baytoro	Building Bridges (CEOI17_building)	C++17	100 / 100	44 ms	10844 KiB

building

#include <bits/stdc++.h>
using namespace std;
#define ios ios::sync_with_stdio(false); cin.tie(NULL);cout.tie(NULL);
#define pb push_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define fr first
#define sc second
#define endl '\n'
#define ll long long
#define int long long
void fopn(string name){
    freopen((name+".in").c_str(),"r",stdin);
    freopen((name+".out").c_str(),"w",stdout);
}
const int INF=1e9,mod=998244353;
template <class F, class _S>
bool chmin(F &u, const _S &v){
    bool flag = false;
    if ( u > v ){
        u = v; flag |= true;
    }
    return flag;
}
 
template <class F, class _S>
bool chmax(F &u, const _S &v){
    bool flag = false;
    if ( u < v ){
        u = v; flag |= true;
    }
    return flag;
}
 
const int inf = 1e18;
 
const int C = 2e6;
 
struct Lichao{
    struct Line{
        int m, c;
 
        Line(int m = 0, int c = inf) : m(m), c(c) {}
 
        int operator ()(int x){ return m * x + c; }
    };
    struct Info{
        Line sg;
 
        Info *lf, *rg;
 
        Info(Line sg) : sg(sg), lf(0), rg(0) {}
    };
    Info *root = new Info({0, inf});
    void ins(Info *v, int l, int r, Line nw){
        if ( l == r ){
            if ( v->sg(l) > nw(l) ){
                v->sg = nw;
            } return;
        }
        int md = (l + r) >> 1;
        if ( v->sg.m > nw.m ) swap(v->sg, nw);
        if ( v->sg(md) <= nw(md) ){
            if ( v->lf ){
                ins(v->lf, l, md, nw);
            } else v->lf = new Info(nw);
        } else{
            swap(v->sg, nw);
            if ( v->rg ){
                ins(v->rg, md + 1, r, nw);
            } else v->rg = new Info(nw);
        }
    }
    void ins(Line nw){
        ins(root, -C, C, nw);
    }
 
    int get(Info *v, int l, int r, int x){
        if ( l == r ){
            return v->sg(x);
        }
        int md = (l + r) >> 1, ret = v->sg(x);
        if ( x <= md ){
            if ( v->lf ){
                chmin(ret, get(v->lf, l, md, x));
            }
        } else{
            if ( v->rg ){
                chmin(ret, get(v->rg, md + 1, r, x));
            }
        } return ret;
    }
    int get(int x){
        return get(root, -C, C, x);
    }
 
    void clear(){ root = new Info ({0, inf}); }
};
const int N=2e5+5;
ll h[N],b[N],pref[N];
void solve(){
	int n;cin>>n;
	for(int i=0;i<n;i++){
		cin>>h[i];
	}
	Lichao tree;
	for(int i=0;i<n;i++){
		cin>>b[i];
		if(i)
			pref[i]=pref[i-1]+b[i];
		else
			pref[i]=b[i];
	}
	vector<int> dp(n);
	auto ad = [&](int j){
		tree.ins({-2*h[j],h[j]*h[j]-pref[j]+dp[j]});
	};
	ad(0);
	for(int i=1;i<n;i++){
		dp[i]=tree.get(h[i])+h[i]*h[i]+pref[i-1];
		ad(i);
	}
	/*for(int i=0;i<n;i++)
		cout<<dp[i]<<' ';
	cout<<endl;*/
	cout<<dp[n-1];
}
main(){
    ios;
    int T=1;
    //cin>>T;
    while(T--){
        solve();
    }
}
/*
6
3 8 7 1 6 6
0 -1 9 1 2 0
11
7958 4722 9704 6995 1052 5269 7479 8238 6423 7918 866
7659 2498 8486 1196 7462 6633 2158 2022 1146 8392 3037
*/

컴파일 시 표준 에러 (stderr) 메시지

building.cpp:128:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  128 | main(){
      | ^~~~
building.cpp: In function 'void fopn(std::string)':
building.cpp:13:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 |     freopen((name+".in").c_str(),"r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
building.cpp:14:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 |     freopen((name+".out").c_str(),"w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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