oj.uz

Submission #658385

# Submission time Handle Problem Language Result Execution time Memory
658385 2022-11-13T04:28:26 Z TheEpicCowOfLife Robot (JOI21_ho_t4) C++14
100 / 100
 968 ms 96824 KB 
#include <bits/stdc++.h>

// #ifdef DEBUG
// #define D(..) = printf(..)
// #else
// #define D(..) = printf(..)
// #endif
using namespace std;

int n,m;
typedef long long ll;
typedef pair<ll, ll> pll;

// price, target
map<int,vector<pll>> g[100005];

map<int,ll> tc[100005];

/// final graph to dijkstra over
vector<pll> fg[100005];


// Observations: You want to reach each node at most once
// You can always assign a new unique edge 
// At each node you have two choices: Assign every other edge, and take the edge for free,
// or just assign

inline void add_edge(int u, int v, int c, long long p){
    if (g[u].find(c) == g[u].end()){
        vector<pll> vec;
        vec.push_back({p,v});
        g[u][c] = vec;
        tc[u][c] = p;
    }
    else{
        g[u][c].push_back({p,v});
        tc[u][c] += p;
    }
}
inline void add_change_edge(int u, int v, int c, long long p){
    // Add edge from u -> v
    fg[u].push_back({v,p});
    // printf("Added change base %d-%lld %lld\n", u, v, p);
    // I'm pretty sure you only need to consider the top 2 weights, but the math seems ab it tight and 
    // idk if I have all the cases considered

    // ll maxw = g[u][c][0].first;
    for (int i = 0; i < min(4,(int) g[v][c].size()); i++){
        ll tgt = g[v][c][i].second;
        ll w = g[v][c][i].first;
        if (tgt == u){
            continue; // don't do a back-edge
        }
        // New edge: Go from u to v to tgt, where we change u -> v, and don't change v -> tgt
        fg[u].push_back({tgt, tc[v][c] - w});

        // printf("Added change case %d-%lld %lld\n", u, tgt, tc[v][c] - w);
    }
}

ll dist[100005];
bool explored[100005];

priority_queue<pll,vector<pll>,greater<pll>> q;

int main(){
    scanf("%d %d", &n, &m);

    for (int i = 1; i <= m; i++){
        int u,v,c;
        long long p;        
        scanf("%d %d %d %lld", &u,&v,&c,&p);
        add_edge(u,v,c,p);
        add_edge(v,u,c,p);
    }

    for (int i = 1; i <= n; i++){
        dist[i] = 1e18;
        // sort the vecs
        for (auto cur : g[i]){
            int c = cur.first;
            sort(g[i][c].begin(),g[i][c].end(), greater<pll>());
        }
    }

    for (int i = 1; i <= n; i++){
        for (auto cur : g[i]){
            int c = cur.first;            
            for (auto thing : cur.second){
                ll v = thing.second;
                ll p = thing.first;
                add_change_edge(i,v,c,p);
                fg[i].push_back({v,tc[i][c] - p});
                // printf("%lld %lld %lld\n", i, v , p);
            }
        }              
    }

    // for (int i = 1; i <= n; i++){
    //     for (auto tgt : fg[i]){
    //     }
    // }

    dist[1] = 1;
    q.push({0,1});
    while (!q.empty()){
        auto cur = q.top();
        q.pop();
        long long d = cur.first;
        long long x = cur.second;
        if (explored[x]){
            continue;
        }
        explored[x] = true;
        for (auto tgt : fg[x]){
            ll tdist = tgt.second + d;
            if (!explored[tgt.first] && tdist < dist[tgt.first]){
                q.push({tdist,tgt.first});
                dist[tgt.first] = tdist;
            }
        }       
    }
    if (dist[n] > 9e17){
        printf("-1\n");
    }
    else{
        printf("%lld\n", dist[n]);
    }
}

Compilation message

Main.cpp: In function 'int main()':
Main.cpp:67:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   67 |     scanf("%d %d", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~~
Main.cpp:72:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   72 |         scanf("%d %d %d %lld", &u,&v,&c,&p);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
34.0 / 34.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11988 KB Output is correct
2 Correct 5 ms 11988 KB Output is correct
3 Correct 6 ms 11988 KB Output is correct
4 Correct 5 ms 11988 KB Output is correct
5 Correct 6 ms 12104 KB Output is correct
6 Correct 5 ms 11988 KB Output is correct
7 Correct 7 ms 12272 KB Output is correct
8 Correct 6 ms 12116 KB Output is correct
9 Correct 9 ms 12756 KB Output is correct
10 Correct 9 ms 12756 KB Output is correct
11 Correct 7 ms 12628 KB Output is correct
12 Correct 7 ms 12660 KB Output is correct
13 Correct 7 ms 12704 KB Output is correct
14 Correct 8 ms 12628 KB Output is correct
15 Correct 7 ms 12372 KB Output is correct
16 Correct 8 ms 12700 KB Output is correct
17 Correct 10 ms 12628 KB Output is correct
18 Correct 8 ms 12188 KB Output is correct
19 Correct 8 ms 12628 KB Output is correct
20 Correct 7 ms 12500 KB Output is correct

Subtask #2
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 207 ms 40392 KB Output is correct
2 Correct 85 ms 24772 KB Output is correct
3 Correct 251 ms 58292 KB Output is correct
4 Correct 131 ms 31012 KB Output is correct
5 Correct 917 ms 86428 KB Output is correct
6 Correct 716 ms 82364 KB Output is correct
7 Correct 342 ms 76012 KB Output is correct
8 Correct 548 ms 82112 KB Output is correct
9 Correct 577 ms 82144 KB Output is correct
10 Correct 372 ms 56112 KB Output is correct
11 Correct 233 ms 46028 KB Output is correct

Subtask #3
42.0 / 42.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11988 KB Output is correct
2 Correct 5 ms 11988 KB Output is correct
3 Correct 6 ms 11988 KB Output is correct
4 Correct 5 ms 11988 KB Output is correct
5 Correct 6 ms 12104 KB Output is correct
6 Correct 5 ms 11988 KB Output is correct
7 Correct 7 ms 12272 KB Output is correct
8 Correct 6 ms 12116 KB Output is correct
9 Correct 9 ms 12756 KB Output is correct
10 Correct 9 ms 12756 KB Output is correct
11 Correct 7 ms 12628 KB Output is correct
12 Correct 7 ms 12660 KB Output is correct
13 Correct 7 ms 12704 KB Output is correct
14 Correct 8 ms 12628 KB Output is correct
15 Correct 7 ms 12372 KB Output is correct
16 Correct 8 ms 12700 KB Output is correct
17 Correct 10 ms 12628 KB Output is correct
18 Correct 8 ms 12188 KB Output is correct
19 Correct 8 ms 12628 KB Output is correct
20 Correct 7 ms 12500 KB Output is correct
21 Correct 207 ms 40392 KB Output is correct
22 Correct 85 ms 24772 KB Output is correct
23 Correct 251 ms 58292 KB Output is correct
24 Correct 131 ms 31012 KB Output is correct
25 Correct 917 ms 86428 KB Output is correct
26 Correct 716 ms 82364 KB Output is correct
27 Correct 342 ms 76012 KB Output is correct
28 Correct 548 ms 82112 KB Output is correct
29 Correct 577 ms 82144 KB Output is correct
30 Correct 372 ms 56112 KB Output is correct
31 Correct 233 ms 46028 KB Output is correct
32 Correct 193 ms 62296 KB Output is correct
33 Correct 205 ms 54684 KB Output is correct
34 Correct 418 ms 66496 KB Output is correct
35 Correct 317 ms 57052 KB Output is correct
36 Correct 317 ms 61560 KB Output is correct
37 Correct 340 ms 74556 KB Output is correct
38 Correct 333 ms 79660 KB Output is correct
39 Correct 219 ms 75244 KB Output is correct
40 Correct 567 ms 87396 KB Output is correct
41 Correct 585 ms 87532 KB Output is correct
42 Correct 561 ms 81356 KB Output is correct
43 Correct 270 ms 48768 KB Output is correct
44 Correct 486 ms 82492 KB Output is correct
45 Correct 452 ms 68888 KB Output is correct
46 Correct 388 ms 61788 KB Output is correct
47 Correct 341 ms 73204 KB Output is correct
48 Correct 968 ms 96824 KB Output is correct