Submission #46492

#	Time	Username	Problem	Language	Result	Execution time	Memory
46492		RockyB	Building Bridges (CEOI17_building)	C++17	100 / 100	78 ms	7652 KiB

building

/// In The Name Of God

#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#include <bits/stdc++.h>

#define f first
#define s second

#define pb push_back
#define pp pop_back
#define mp make_pair

#define sz(x) (int)x.size()
#define sqr(x) ((x) * 1ll * (x))
#define all(x) x.begin(), x.end()

#define Kazakhstan ios_base :: sync_with_stdio(0), cin.tie(0), cout.tie(0);

#define nl '\n'
#define ioi exit(0);

typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;

const int N = (int)1e5 + 7;
const int K = 1;
const int inf = (int)1e9 + 7;
const int mod = (int)1e9 + 7;
const ll linf = (ll)1e18 + 7;

const int dx[] = {-1, 0, 1, 0, 1, -1, -1, 1};
const int dy[] = {0, 1, 0, -1, 1, -1, 1, -1};

using namespace std;

int n;
int h[N], w[N];
ll dp[N], s[N];

struct line {
	ll k, b;
	line() {
		k = 0, b = linf;
	}
	line(ll k, ll b) : k(k), b(b) {}
	ll get(ll x) {
		return k * x + b;
	}
};

struct tree {
	struct node {
		node *l, *r;
		line x;
		node(line x) : x(x) {
			l = r = 0;
		}
	};
	node *t;

	inline void upd(line x, node *&v, int tl = -2e6, int tr = 2e6) {
		if (!v) {
			v = new node(x);
			return;
		}

		int tm = tl + tr >> 1;
		bool lf = x.get(tl) < v -> x.get(tl);
		bool md = x.get(tm) < v -> x.get(tm);
		if (md) swap(x, v -> x);
		if (tl == tr) return;
		if (lf != md) upd(x, v -> l, tl, tm);
		else upd(x, v -> r, tm + 1, tr);
	}
	inline ll get(int p, node *&v, int tl = -2e6, int tr = 2e6) {
		if (!v) return linf;
		if (tl == tr) return v -> x.get(p);
		int tm = tl + tr >> 1;
		if (p <= tm) return min(get(p, v -> l, tl, tm), v -> x.get(p));
		return min(get(p, v -> r, tm + 1, tr), v -> x.get(p));
	}
	ll get(int p) {
		return get(p, t);
	}
	void upd(line x) {
		upd(x, t);
	}
	inline void clear() {
		t = new node(line(0, linf));
	}
} t;

int main() {
	#ifdef IOI2018
		freopen ("in.txt", "r", stdin);
		//freopen ("A.out", "w", stdout);
	#endif
	Kazakhstan
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> h[i];
	}
	for (int i = 1; i <= n; i++) {
		cin >> w[i];
		s[i] = s[i - 1] + w[i];
	}
	memset(dp, 0x3f, sizeof(dp));
	dp[1] = 0;
	t.upd({h[1], sqr(h[1]) + dp[1] - s[1]});
	for (int i = 2; i <= n; i++) {
		dp[i] = t.get(-2 * h[i]) + sqr(h[i]) + s[i - 1];
		t.upd({h[i], sqr(h[i]) + dp[i] - s[i]});
		/*ll add = 0;
		for (int j = i - 1; j >= 1; j--) {
			dp[i] = min(dp[i], sqr(h[i] - h[j]) + (s[i - 1] - s[j]) + dp[j]);
			add += w[j];
		}*/
	}
	cout << dp[n];
	ioi
}

Compilation message (stderr)

building.cpp: In member function 'void tree::upd(line, tree::node*&, int, int)':
building.cpp:70:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   int tm = tl + tr >> 1;
            ~~~^~~~
building.cpp: In member function 'll tree::get(int, tree::node*&, int, int)':
building.cpp:81:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   int tm = tl + tr >> 1;
            ~~~^~~~

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