Submission #882685

#	Time	Username	Problem	Language	Result	Execution time	Memory
882685		aeg	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	57 / 100	1072 ms	21716 KiB

skyscraper

#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,popcnt,lzcnt")
#include <bits/stdc++.h>
using namespace std;

const int MAXM = 3e4+5, MAXN = 3e4+5;

int n, p[MAXM], m, secloc;
vector<int> a(MAXN, INT_MAX);
queue<int> b[MAXN];

struct triple {
	int first, second;
	char third;
	triple() : first(0), second(0), third(0) {}
	triple(int a, int b, char c) :first(a), second(b), third(c) {}
};

queue<triple> curr, oth;

signed main() {
	cin.tie(0)->sync_with_stdio(0);
	cin >> n >> m;
	for(int i = 0; i < m; i++) {
		int tmp;
		cin >> tmp >> p[i];
		if(i==0) curr.push({tmp, p[0], 3});
		b[tmp].push(i);
		if(i==1) secloc = tmp;
	}
	int curval = 0;
	while(!curr.empty()) {
		auto cur = curr.front(); curr.pop();
		if(a[cur.first] == INT_MAX) {
			while(!b[cur.first].empty()) {
				int x = b[cur.first].front();
				b[cur.first].pop();
				if(p[x] != cur.second)
					curr.push({cur.first, p[x], 3});
			}
		}
		a[cur.first] = min(a[cur.first], curval);
		if(cur.first >= cur.second && cur.third != 2)
			oth.push({cur.first - cur.second, cur.second, 1});
		if(cur.first < n - cur.second && cur.third != 1)
			oth.push({cur.first + cur.second, cur.second, 2});
		if(curr.empty()) {
			swap(curr, oth);
			curval ++;
		}
	}
	cout << (a[secloc] == INT_MAX ? -1 : a[secloc]) << '\n';
}

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 14 / 14
• Subtask 4: 21 / 21
• Subtask 5: 0 / 43