Submission #171726

#	Time	Username	Problem	Language	Result	Execution time	Memory
171726		dsjong	Sky Walking (IOI19_walk)	C++14	10 / 100	4075 ms	835976 KiB

walk

#include "walk.h"
#include <bits/stdc++.h>
using namespace std;
 
map<pair<int,int>,int> mp;
vector<pair<int,int>>adj[1000005];
long long dis[1000005];
long long INF=LONG_LONG_MAX;
bool vis[1000005];
void dijkstra(int source){
	class prioritize{
		public: bool operator ()(pair<int,long long>&p1 ,pair<int,long long>&p2){
			return p1.second>p2.second;
		}
	};
	for(int i=0;i<=1000000;i++) dis[i]=INF;
	priority_queue<pair<int,long long>,vector<pair<int,long long>>,prioritize>pq;
	dis[source]=0;
	pq.push({source,0});
	while(!pq.empty()){
		pair<int,long long>curr=pq.top();
		pq.pop();
		int cv=curr.first;
		long long cw=curr.second;
		if(vis[cv]) continue;
		vis[cv]=true; 
		for(auto i:adj[cv]){
			if(vis[i.first]) continue;
			if(i.second+cw<dis[i.first]){
				dis[i.first]=i.second+cw;
				//cout<<i.first<<" "<<dis[i.first]<<endl;
				pq.push({i.first,dis[i.first]});
			}
		}
	}
}
long long min_distance(vector<int> x, vector<int> h, vector<int> l, vector<int> r, std::vector<int> y, int s, int g) {
	vector<pair<int,int>>all;
	int n = x.size(), m = l.size();
	mp[{s,0}]=0;
	mp[{g,0}]=1;
	int cnt = 2;
	all.push_back({s,0});
	all.push_back({g,0});
	for(int i = 0; i < m; i++){
		int last=-1;
		for(int j = l[i]; j <= r[i]; j++){
			if(!mp[{j, y[i]}] && h[j] >= y[i]){
				all.push_back({j, y[i]});
				mp[{j, y[i]}] =cnt;
				//cout<<mp[{j,y[i]}]<<endl;
				cnt++;
			}
			if(h[j]>=y[i]){
				if(last!=-1){
					adj[mp[{j,y[i]}]].push_back({mp[{last,y[i]}],x[j]-x[last]});
					adj[mp[{last,y[i]}]].push_back({mp[{j,y[i]}],x[j]-x[last]});
					//cout<<mp[{j,y[i]}]<<" "<<mp[{last,y[i]}]<<" "<<x[j]-x[last]<<endl;
				}
				last = j;
			}
		}
	}
	//cout<<e;
	sort(all.begin(),all.end());
	for(int i=1; i < all.size(); i++){
		if(all[i].first == all[i-1].first){
			adj[mp[all[i]]].push_back({mp[all[i-1]], all[i].second-all[i-1].second});
			adj[mp[all[i-1]]].push_back({mp[all[i]], all[i].second-all[i-1].second});
		}
	}
	dijkstra(0);
	if(dis[1]==INF) return -1;
	return dis[1];
}

Compilation message (stderr)

walk.cpp: In function 'long long int min_distance(std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>, int, int)':
walk.cpp:66:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=1; i < all.size(); i++){
               ~~^~~~~~~~~~~~
walk.cpp:39:6: warning: unused variable 'n' [-Wunused-variable]
  int n = x.size(), m = l.size();
      ^

• Subtask 1: 10 / 10
• Subtask 2: 0 / 14
• Subtask 3: 0 / 15
• Subtask 4: 0 / 18
• Subtask 5: 0 / 43