Submission #1098637

#	Time	Username	Problem	Language	Result	Execution time	Memory
1098637		flyingkite	Robot (JOI21_ho_t4)	C++17	100 / 100	1246 ms	126200 KiB

Main

#include <bits/stdc++.h>
using namespace std;
 
#define ll long long
#define pll pair<long long, long long>
#define pb push_back
#define F first
#define S second  
#define all(x) (x).begin(), (x).end()
const ll N = 2e5 + 100;
const ll inf = 1e18;
const ll mod = 1e9 + 7;
const ll block = 350;
ll n,m;
struct ccjv{ll v,c,p;};
struct ngu{ll u,c,col;};
map<ll,ll>d[N];
struct cmp{
    bool operator()(const ngu &a, const ngu &b){
        return a.c > b.c;
    }
};
map<ll, vector<ccjv>>g[N];
vector<ccjv>adj[N];
map<ll,ll>mp[N];
void to_thic_cau(){
    cin >> n >> m;
    for(int i = 1; i <= m;i++){
        ll u,v,c,p; cin >> u >> v >> c >> p;
        mp[u][c] += p; mp[v][c] += p;
        adj[u].pb({v,c,p}); adj[v].pb({u,c,p});
        g[u][c].pb({v,c,p}); g[v][c].pb({u,c,p});
    }
    for(int i = 1; i <= n;i++){
        for(auto j : adj[i]) d[i][j.c] = inf;
        d[i][0] = inf;
    }
    d[1][0] = 0;
    priority_queue<ngu, vector<ngu>, cmp>q;
    q.push({1, d[1][0], 0});
    while(q.size()){
        ll u = q.top().u, cost = q.top().c, col = q.top().col; q.pop();
        if(cost != d[u][col]) continue;
        if(col == 0){
            for(auto x : adj[u]){
                ll v = x.v, c = x.c, p = x.p;
                // di nhu bthg
                if(d[v][0] > d[u][0] + min(p, mp[u][c] - p)){
                    d[v][0] = d[u][0] + min(p, mp[u][c] - p);
                    q.push({v, d[v][0], 0});
                }     
                // thay mau canh
                if(d[v][c] > d[u][0]){
                    d[v][c] = d[u][0];
                    q.push({v, d[v][c], c});
                }
            }
        }
        else{
            for(auto x : g[u][col]){
                ll v = x.v, c = x.c, p = x.p;
                if(d[u][col] + mp[u][col] - p < d[v][0]){
                    d[v][0] = d[u][col] + mp[u][col] - p;
                    q.push({v, d[v][0], 0});
                }      
            }
        }
    }
    cout << (d[n][0] == inf ? -1 : d[n][0]) << "\n";
}
 
signed main()   
{  
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    ll tc = 1;
    //cin >> tc;
    while(tc--) to_thic_cau();
}

Compilation message (stderr)

Main.cpp: In function 'void to_thic_cau()':
Main.cpp:61:29: warning: unused variable 'c' [-Wunused-variable]
   61 |                 ll v = x.v, c = x.c, p = x.p;
      |                             ^

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