oj.uz

답안 #839684

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
839684 2023-08-30T12:51:39 Z bLIC Building Bridges (CEOI17_building) C++17
100 / 100
 42 ms 10572 KB 
/**
 *  Author: Anil Byar
**/

#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>

// using namespace __gnu_pbds;
using namespace std;

// template<class T>
// using ordered_set = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;



#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)(x).size()
#define uniq(v) v.erase(unique(all(v)), v.end())
#define ft first
#define sd second
#define pb push_back
#define eb emplace_back

// Source: https://codeforces.com/blog/entry/68809
// { start
void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '"' << x << '"';}
void __print(const string &x) {cerr << '"' << x << '"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif
// } end


typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii> vii;
typedef vector<ll> vl;
typedef vector<pll> vll;
typedef vector<vi> vvi;
typedef vector<vii> vvii;
typedef vector<vl> vvl;

#define dbg if(0)

const ll MOD = 1e9+7;
const ll MOD9 = 998244353;
const ll INFLL = 1e18+5;
const int INF = 1e9;

void printbit(int x, int len) {string s="\n";while(len--){s=((x%2)?'1':'0')+s;x/=2;} cout<<s;}
ll power(ll x, ll y, ll mod){if (y==0) return 1;ll ret = power(x, y/2, mod);ret *= ret;ret%=mod;if (y&1) ret *= x;return ret%mod;}
ll modinv(ll x, ll mod = MOD) {return power(x, mod-2, mod);}

template<class T> bool chmin(T& a, T b){return (a>b?a=b,1:0);}
template<class T> bool chmax(T& a, T b){return (a<b?a=b,1:0);}
template<class T>
istream& operator>>(istream&in, vector<T>&v){
	for (T& x:v) in>>x;
	return in;
}
template<class T>
ostream& operator<<(ostream&out, vector<T>&v){
	for (T& x:v) out<<x<<' ';
	cout<<'\n';
	return out;
}
// use ?: with brackets (?:)
// check for overflow
// think about dp
// Read the statement carefully


/**
 * Author: Simon Lindholm
 * Date: 2017-04-20
 * License: CC0
 * Source: own work
 * Description: Container where you can add lines of the form kx+m, and query maximum values at points x.
 *  Useful for dynamic programming (``convex hull trick'').
 * Time: O(\log N)
 * Status: stress-tested
 */

struct Line {
	mutable ll k, m, p;
	bool operator<(const Line& o) const { return k > o.k; }
	bool operator<(ll x) const { return p < x; }
};

struct LineContainer : multiset<Line, less<>> {
	// (for doubles, use inf = 1/.0, div(a,b) = a/b)
	static const ll inf = LLONG_MAX;
	ll div(ll a, ll b) { // floored division
		return a / b - ((a ^ b) < 0 && a % b); }
	bool isect(iterator x, iterator y) {
		if (y == end()) return x->p = inf, 0;
		if (x->k == y->k) x->p = x->m < y->m ? inf : -inf;
		else x->p = div(y->m - x->m, x->k - y->k);
		return x->p >= y->p;
	}
	void add(ll k, ll m) {
		auto z = insert({k, m, 0}), y = z++, x = y;
		while (isect(y, z)) z = erase(z);
		if (x != begin() && isect(--x, y)) isect(x, y = erase(y));
		while ((y = x) != begin() && (--x)->p >= y->p)
			isect(x, erase(y));
	}
	ll query(ll x) {
		assert(!empty());
		auto l = *lower_bound(x);
		return l.k * x + l.m;
	}
};


void solve(){
	int n;cin>>n;
	vl h(n), w(n);
	vl pref(n);
	cin>>h>>w;
	pref[0] = w[0];
	for (int i = 1;i<n;i++) pref[i] = pref[i-1] + w[i];
	ll dp[n+1]{};
	LineContainer chull;
	dp[1] = 0;
	chull.add(-2*h[0], dp[0] + h[0] * h[0] - pref[0]);
	for (int i = 1;i<n;i++) {
		dp[i] = h[i] * h[i] + pref[i-1] + chull.query(h[i]);
		chull.add(-2*h[i], dp[i] + h[i] * h[i] - pref[i]);
	}
	cout<<dp[n-1];
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
	cout.tie(nullptr);


#define ONLINE_JUDGE
#ifndef ONLINE_JUDGE
	freopen("input.in", "r", stdin);
	freopen("output.out", "w", stdout);
	freopen("debug.dbg", "w", stderr);
	int tt = clock();
#endif

	int t=1, i = 1;
	// cin>>t;
	while(t--){
		// cout<<"Case #"<<i++<<": ";
		solve();
		cout<<'\n';
	}
#ifndef ONLINE_JUDGE
	cerr << "TIME = " << (float)(clock() - tt)/CLOCKS_PER_SEC << endl;
	tt = clock();
#endif
}

Compilation message

building.cpp: In function 'int main()':
building.cpp:173:11: warning: unused variable 'i' [-Wunused-variable]
  173 |  int t=1, i = 1;
      |           ^

Subtask #1
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct

Subtask #2
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 30 ms 3528 KB Output is correct
2 Correct 31 ms 4436 KB Output is correct
3 Correct 30 ms 4536 KB Output is correct
4 Correct 28 ms 4308 KB Output is correct
5 Correct 26 ms 5588 KB Output is correct

Subtask #3
40.0 / 40.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 30 ms 3528 KB Output is correct
7 Correct 31 ms 4436 KB Output is correct
8 Correct 30 ms 4536 KB Output is correct
9 Correct 28 ms 4308 KB Output is correct
10 Correct 26 ms 5588 KB Output is correct
11 Correct 36 ms 4680 KB Output is correct
12 Correct 30 ms 4436 KB Output is correct
13 Correct 25 ms 4576 KB Output is correct
14 Correct 36 ms 4692 KB Output is correct
15 Correct 42 ms 10572 KB Output is correct
16 Correct 29 ms 5580 KB Output is correct
17 Correct 17 ms 4436 KB Output is correct
18 Correct 17 ms 4436 KB Output is correct