Submission #1050940

#	Time	Username	Problem	Language	Result	Execution time	Memory
1050940		Itamar	Sky Walking (IOI19_walk)	C++14	0 / 100	3265 ms	331828 KiB

walk

using namespace std;
#include <bits/stdc++.h>
#define ll long long
#define vll vector<ll>
#define pll pair<ll,ll>
#define pi pair<ll,ll>
#define vi vector<int>
long long min_distance(std::vector<int> x, std::vector<int> h, std::vector<int> l, std::vector<int> r, std::vector<int> y, int s, int g) {
	int n = x.size(), m = l.size();
    map<pi,vector<pi>> fr;
    multiset<pi> poi;
    vector<vector<pi>> ins(2e5+2);
    vector<vector<pi>> rem(2e5+2);
    for(int i = 0; i < m; i++){
        ins[l[i]].push_back({y[i],i});
        rem[r[i]].push_back({y[i],i});
    }
    map<int,int> prev;
    for(int i = 0; i < n; i++){
        for(pi hei : ins[i])poi.insert(hei);
        pi bel = {x[i],0};
        auto it = poi.begin();
        while(it!=poi.end() && (*it).first <= h[i]){
            int cur = (*it).first;
            pi p = {x[i],cur};
            fr[p].push_back(bel);
            fr[bel].push_back(p);
            if(l[(*it).second]!=i){
                fr[p].push_back({prev[cur],cur});
                fr[{prev[cur],cur}].push_back(p);
            }
            prev[cur]=x[i];
            bel = p;
            it++;
        }
        for(pi hei : rem[i])poi.erase(poi.find(hei));
    }
    map<pi,ll> dp;
    for(auto[a,b] : fr)dp[a]=1e18;
    dp[{x[g],0}]=1e18;
    dp[{x[s],0}]=0;
    set<pair<ll,pi>> se;
    map<pi,bool> vis;
    se.insert({0,{x[s],0}});
    while(!se.empty()){
        pair<ll,pi> p = *se.begin();
        pi q = p.second;
        se.erase(se.begin());
        if(vis[q])continue;
        vis[q]=1;
        for(pi f : fr[q]){
            if(vis[f])continue;
            ll w = dp[q] + (abs(f.first-q.first)+abs(f.second-q.second));
            se.insert({w,f});
            dp[f] = min(dp[f],w);
        }
    }
    if(dp[{x[g],0}]==0 || dp[{x[g],0}]>=1e16)return -1;
    return dp[{x[g],0}];
}

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:39:13: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   39 |     for(auto[a,b] : fr)dp[a]=1e18;
      |             ^

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