Submission #536793

#	Time	Username	Problem	Language	Result	Execution time	Memory
536793		Gurban	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	57 / 100	1100 ms	82632 KiB

skyscraper

// #pragma GCC optimize("Ofast")
// #pragma GCC target("avx,avx2,fma")
#include "bits/stdc++.h"
using namespace std;
 
using ll = long long;
 
const int maxn=3e4+5;
int n,m;
int b[maxn],p[maxn];
vector<int>v[maxn];

struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        // http://xorshift.di.unimi.it/splitmix64.c
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

unordered_map<int,int,custom_hash>dis;
 
int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
 
	cin >> n >> m;
	int mx = max(n,m) + 1;
	for(int i = 0;i < m;i++){
		cin >> b[i] >> p[i];
		v[b[i]].push_back(p[i]);
	}
	queue<pair<int,int>>q;
	q.push({b[0],p[0]});
	dis[b[0] * mx + p[0]] = 0;
	while(!q.empty()){
		int idx = q.front().first;
		int pi = q.front().second;
		q.pop();
		int now = dis[idx * mx + pi];
		if(idx == b[1]) return cout<<now,0;
		if(idx - pi >= 0){
			auto t = dis.find((idx - pi) * mx + pi);
			if(t == dis.end() or (t != dis.end() and (*t).second > now + 1)){
				dis[(idx - pi) * mx + pi] = now + 1;
				q.push({idx - pi,pi});
			}
		}
		if(idx + pi < n){
			auto t = dis.find((idx + pi) * mx + pi);
			if(t == dis.end() or (t != dis.end() and (*t).second > now + 1)){
				dis[(idx + pi) * mx + pi] = now + 1;
				q.push({idx + pi,pi});
			}
		}
		for(auto i : v[idx]){
			if(idx - i >= 0){
				auto t = dis.find((idx - i) * mx + i);
				if(t == dis.end() or (t != dis.end() and (*t).second > now + 1)){
					dis[(idx - i) * mx + i] = now + 1;
					q.push({idx - i,i});
				}		
			}
			if(idx + i < n){
				auto t = dis.find((idx + i) * mx + i);
				if(t == dis.end() or (t != dis.end() and (*t).second > now + 1)){
					dis[(idx + i) * mx + i] = now + 1;
					q.push({idx + i,i});
				}
			}
		}
	}
	cout<<-1;
}

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