Submission #754253

#	Time	Username	Problem	Language	Result	Execution time	Memory
754253		MetalPower	Global Warming (CEOI18_glo)	C++14	17 / 100	238 ms	12636 KiB

glo

#include <bits/stdc++.h>
using namespace std;

const int MX = 2e5 + 10;
const int INF = 1e9 + 7;

struct segtree{
	int st[MX << 2], lz[MX << 2];

	void build(int id, int l, int r){
		if(l == r){
			st[id] = -INF;
			lz[id] = 0;
		}else{
			int mid = l + r >> 1;
			build(id << 1, l, mid);
			build(id << 1|1, mid + 1, r);
			st[id] = max(st[id << 1], st[id << 1|1]);
		}
	}

	void prop(int id, int l, int r){
		if(lz[id] == 0) return;
		st[id] += lz[id];
		if(l != r){
			lz[id << 1] += lz[id];
			lz[id << 1|1] += lz[id];
		}
		lz[id] = 0;
	}

	void upd_pos(int id, int l, int r, int p, int v){
		prop(id, l, r);
		if(r < p || l > p) return;
		if(l == p && p == r){
			st[id] = v;
		}else{
			int mid = l + r >> 1;
			upd_pos(id << 1, l, mid, p, v);
			upd_pos(id << 1|1, mid + 1, r, p, v);
			st[id] = max(st[id << 1], st[id << 1|1]);
		}
	}

	void upd(int id, int l, int r, int from, int to, int v){
		prop(id, l, r);
		if(r < from || l > to) return;
		if(from <= l && r <= to){
			lz[id] += v;
			prop(id, l, r);
		}else{
			int mid = l + r >> 1;
			upd(id << 1, l, mid, from, to, v);
			upd(id << 1|1, mid + 1, r, from, to, v);
			st[id] = max(st[id << 1], st[id << 1|1]);
		}
	}

	int que(int id, int l, int r, int from, int to){
		prop(id, l, r);
		if(r < from || l > to) return -INF;
		if(from <= l && r <= to){
			return st[id];
		}else{
			int mid = l + r >> 1;
			return max(
				que(id << 1, l, mid, from, to),
				que(id << 1|1, mid + 1, r, from, to)
			);
		}
	}
} S, T;

void chmax(int& a, int b){
	if(b > a) a = b;
}

vector<int> cc;
int N, X, arr[MX], pref[MX], suff[MX];

int main(){
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

	cin >> N >> X;
	for(int i = 0; i < N; i++){
		cin >> arr[i];
		cc.push_back(arr[i]);
	}

	cc.push_back(0);
	sort(cc.begin(), cc.end());
	cc.resize(unique(cc.begin(), cc.end()) - cc.begin());

	S.build(1, 0, N);

	S.upd_pos(1, 0, N, 0, 0);
	for(int i = 0; i < N; i++) arr[i] = lower_bound(cc.begin(), cc.end(), arr[i]) - cc.begin();

	for(int i = 0; i < N; i++){
		pref[i] = S.que(1, 0, N, 0, arr[i] - 1) + 1;
		S.upd_pos(1, 0, N, arr[i], pref[i]);
		if(i > 0) chmax(pref[i], pref[i - 1]);
	}

	T.build(1, 1, N + 1);

	T.upd_pos(1, 1, N + 1, N + 1, 0);
	for(int i = N - 1; i >= 0; i--){
		suff[i] = T.que(1, 1, N + 1, arr[i] + 1, N + 1) + 1;
		T.upd_pos(1, 1, N + 1, arr[i], suff[i]);
		if(i < N - 1) chmax(suff[i], suff[i + 1]);
	}

	int ans = suff[0];
	for(int i = 0; i < N; i++) chmax(ans, pref[i] + suff[i + 1]);
	cout << ans << '\n';
}

Compilation message (stderr)

glo.cpp: In member function 'void segtree::build(int, int, int)':
glo.cpp:15:16: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   15 |    int mid = l + r >> 1;
      |              ~~^~~
glo.cpp: In member function 'void segtree::upd_pos(int, int, int, int, int)':
glo.cpp:38:16: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   38 |    int mid = l + r >> 1;
      |              ~~^~~
glo.cpp: In member function 'void segtree::upd(int, int, int, int, int, int)':
glo.cpp:52:16: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   52 |    int mid = l + r >> 1;
      |              ~~^~~
glo.cpp: In member function 'int segtree::que(int, int, int, int, int)':
glo.cpp:65:16: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   65 |    int mid = l + r >> 1;
      |              ~~^~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 13
• Subtask 4: 0 / 10
• Subtask 5: 0 / 20
• Subtask 6: 17 / 17
• Subtask 7: 0 / 25