Submission #1109107

#	Time	Username	Problem	Language	Result	Execution time	Memory
1109107		InvMOD	Robot (JOI21_ho_t4)	C++14	24 / 100	867 ms	84812 KiB

Main

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

#define fi first
#define se second
#define gcd __gcd
#define sz(v) (int) v.size()
#define pb push_back
#define pi pair<int,int>
#define all(v) (v).begin(), (v).end()
#define compact(v) (v).erase(unique(all(v)), (v).end())
#define FOR(i, a, b) for(int i = (a); i <= (b); i++)
#define dbg(x) "[" #x " = " << (x) << "]"
#define int long long

using ll = long long;
using ld = long double;
using ull = unsigned long long;

template<typename T> bool ckmx(T& a, const T& b){if(a < b) return a = b, true; return false;}
template<typename T> bool ckmn(T& a, const T& b){if(a > b) return a = b, true; return false;}

const int N = 1e5+5;
const ll INF = 1e18;
const int Mx = 2e5+1;


struct Node{
    // color < Mx: some affect in color cost of that color
    int v, cur_dist, color, dist_edge;
    Node(int v = 0, int cur_dist = 0, int color = Mx, int dist_edge = 0): v(v), cur_dist(cur_dist), color(color), dist_edge(dist_edge) {}
    bool operator < (const Node& q) const{
        return cur_dist > q.cur_dist;
    }
};

int n, m;

map<int,int> color_cost[N], dist[N];

map<int, vector<pair<int,int>>> adj[N];

void solve()
{
    cin >> n >> m;

    FOR(i, 1, m){
        int u,v,c,w;
        cin >> u >> v >> c >> w;
        adj[u][c].push_back(make_pair(v, w));
        adj[v][c].push_back(make_pair(u, w));
        color_cost[u][c] += w;
        color_cost[v][c] += w;
    }

    // 2 case: (choose to change u->v and affect v) && (choose to change u->v with no affect to v || choose to change all except u->v and no affect to v)

    priority_queue<Node> pq;

    pq.push(Node(1));
    dist[1][Mx] = 0;

    while(!pq.empty()){
        Node eq = pq.top(); pq.pop();

        int color = eq.color, x = eq.v;
        if(dist[x][color] < eq.cur_dist) continue;

        if(color < Mx){
            int total = color_cost[x][color] - eq.dist_edge;

            for(auto [v, w] : adj[x][color]){
                // no affect to v
                if(!dist[v].count(Mx) || ckmn(dist[v][Mx], dist[x][color] + total - w)){
                    dist[v][Mx] = dist[x][color] + total - w;
                    pq.push(Node(v, dist[v][Mx], Mx, 0));
                }

                if(adj[v].count(color) && (int)adj[v][color].size() > 1){
                    // keep affect v
                    if(!dist[v].count(color) || ckmn(dist[v][color], dist[x][color] + w)){
                        dist[v][color] = dist[x][color] + w;
                        pq.push(Node(v, dist[v][color], color, w));
                    }
                }
            }
        }
        else{
            for(auto [color, list_col] : adj[x]){
                int total = color_cost[x][color];

                for(auto [v, w] : list_col){
                    // don't affect v : change all except x->v or change only x->v
                    if(!dist[v].count(Mx) || ckmn(dist[v][Mx], dist[x][Mx] + total - w)){
                        dist[v][Mx] = dist[x][Mx] + total - w;
                        pq.push(Node(v, dist[v][Mx], Mx, 0));
                    }

                    if(!dist[v].count(Mx) || ckmn(dist[v][Mx], dist[x][Mx] + w)){
                        dist[v][Mx] = dist[x][Mx] + w;
                        pq.push(Node(v, dist[v][Mx], Mx, 0));
                    }

                    if(adj[v].count(color) && (int)adj[v][color].size() > 1){
                        // can affect
                        if(!dist[v].count(color) || ckmn(dist[v][color], dist[x][Mx] + w)){
                            dist[v][color] = dist[x][Mx] + w;
                            pq.push(Node(v, dist[v][color], color, w));
                        }
                    }
                }
            }
        }
    }

    if(!dist[n].size()){
        cout << "-1\n";
    }
    else{
        int answer = INF;
        for(auto [color, last_dist] : dist[n]){
            if(color == Mx) ckmn(answer, last_dist);
        }

        cout << answer <<"\n";
    }
}

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

    #define name "InvMOD"
    if(fopen(name".INP", "r")){
        freopen(name".INP","r",stdin);
        freopen(name".OUT","w",stdout);
    }

    int t = 1; //cin >> t;
    while(t--) solve();
    return 0;
}

Compilation message (stderr)

Main.cpp: In function 'void solve()':
Main.cpp:72:22: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   72 |             for(auto [v, w] : adj[x][color]){
      |                      ^
Main.cpp:89:22: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   89 |             for(auto [color, list_col] : adj[x]){
      |                      ^
Main.cpp:92:26: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   92 |                 for(auto [v, w] : list_col){
      |                          ^
Main.cpp:121:18: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  121 |         for(auto [color, last_dist] : dist[n]){
      |                  ^
Main.cpp: In function 'int main()':
Main.cpp:137:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  137 |         freopen(name".INP","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
Main.cpp:138:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  138 |         freopen(name".OUT","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 34
• Subtask 2: 24 / 24
• Subtask 3: 0 / 42