oj.uz

Submission #378121

# Submission time Handle Problem Language Result Execution time Memory
378121 2021-03-16T03:52:01 Z couplefire Toll (BOI17_toll) C++17
100 / 100
 1708 ms 11756 KB 
#include <bits/stdc++.h>
using namespace std;
#define MAXN 50005
#define BLOCK 500
#define INF 10000000000000000ll

int len, n, m, q;
vector<pair<int, int>> adj[MAXN];
vector<pair<int, int>> revadj[MAXN];
long long dist[MAXN/BLOCK+10][MAXN/BLOCK+10][5][5];

long long bfs(int a, int b){
    if(a >= n || b >= n) return INF;
    if(b/len <= a/len) return INF;
    long long dp[5*BLOCK+100];
    fill(dp, dp+5*BLOCK+100, INF);
    dp[0] = 0;
    queue<int> q;
    q.push(a);
    while(!q.empty() && q.front() < b){
        int v = q.front();
        // cout << v << endl;
        q.pop();
        if(dp[v-a] == INF) continue;
        for(auto u : adj[v]){
            if(dp[u.first-a] == INF){
                // cout << u.first << endl;
                q.push(u.first);
            }
            // cout << u.first << endl;
            dp[u.first-a] = min(dp[u.first-a], dp[v-a]+u.second);
        }
    }
    return dp[b-a];
}

int main(){
    // freopen("a.in", "r", stdin);
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin >> len >> n >> m >> q;
    for(int i = 0; i<m; i++){
        int a, b, w; cin >> a >> b >> w;
        adj[a].push_back({b, w});
        revadj[b].push_back({a, w});
    }
    for(int i = ((n-1)/len/BLOCK)*BLOCK; i>=0; i -= BLOCK){
        for(int a = 0; a<len; a++){
            for(int b = 0; b<len; b++){
                dist[i/BLOCK][i/BLOCK][a][b] = INF;
                if(a == b) dist[i/BLOCK][i/BLOCK][a][b] = 0;
            }
            for(int j = i+BLOCK; j<=(n-1)/len; j+=BLOCK){
                for(int b = 0; b<len; b++){
                    if(j == i+BLOCK){
                        dist[i/BLOCK][j/BLOCK][a][b] = bfs(i*len+a, j*len+b);
                        continue;
                    }
                    dist[i/BLOCK][j/BLOCK][a][b] = INF;
                    for(int c = 0; c<len; c++){
                        dist[i/BLOCK][j/BLOCK][a][b] = min(dist[i/BLOCK][j/BLOCK][a][b], dist[i/BLOCK][j/BLOCK-1][a][c]+dist[j/BLOCK-1][j/BLOCK][c][b]);
                    }
                }
            }
        }
    }
    // cout << ceil((BLOCK+1.0)/BLOCK) << endl;
    while(q--){
        int a, b; cin >> a >> b;
        int ca = a%len, cb = b%len;
        int la = a/len, lb = b/len;
        if(lb <= la){
            cout << -1 << endl;
            continue;
        }
        if(la/BLOCK == lb/BLOCK){
            long long ans = bfs(a, b);
            if(ans == INF) cout << -1 << endl;
            else cout << ans << endl;
            continue;
        }
        // cout << "hi" << endl;
        int na = ceil((la+0.0)/BLOCK)*BLOCK;
        int pb = lb/BLOCK*BLOCK;
        long long dp[5*BLOCK+100];
        fill(dp, dp+5*BLOCK+100, INF);
        dp[0] = 0;
        queue<int> q;
        q.push(a);
        while(!q.empty() && q.front() < na*len+len){
            int v = q.front();
            q.pop();
            if(dp[v-a] == INF) continue;
            for(auto u : adj[v]){
                if(dp[u.first-a] == INF) q.push(u.first);
                dp[u.first-a] = min(dp[u.first-a], dp[v-a]+u.second);
            }
        }
        long long revdp[5*BLOCK+100];
        fill(revdp, revdp+5*BLOCK+100, INF);
        revdp[0] = 0;
        queue<int> revq;
        revq.push(b);
        while(!revq.empty() && revq.front() > pb*len-1){
            int v = revq.front();
            revq.pop();
            if(revdp[b-v] == INF) continue;
            for(auto u : revadj[v]){
                if(revdp[b-u.first] == INF) revq.push(u.first);
                revdp[b-u.first] = min(revdp[b-u.first], revdp[b-v]+u.second);
            }
        }
        long long ans = INF;
        for(int i = 0; i<len; i++){
            for(int j = 0; j<len; j++){
                long long v1, v2;
                if(na*len+i-a < 0) v1 = INF;
                else v1 = dp[na*len+i-a];
                if(b-(pb*len+j) < 0) v2 = INF;
                else v2 = revdp[b-(pb*len+j)];
                ans = min(ans, v1+dist[na/BLOCK][pb/BLOCK][i][j]+v2);
            }
        }
        if(ans == INF) cout << -1 << endl;
        else cout << ans << endl;
    }
}

Compilation message

toll.cpp: In function 'int main()':
toll.cpp:70:13: warning: unused variable 'ca' [-Wunused-variable]
   70 |         int ca = a%len, cb = b%len;
      |             ^~
toll.cpp:70:25: warning: unused variable 'cb' [-Wunused-variable]
   70 |         int ca = a%len, cb = b%len;
      |                         ^~

Subtask #1
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 379 ms 8300 KB Output is correct
2 Correct 2 ms 2668 KB Output is correct
3 Correct 2 ms 2668 KB Output is correct
4 Correct 2 ms 2668 KB Output is correct
5 Correct 8 ms 2796 KB Output is correct
6 Correct 7 ms 2796 KB Output is correct
7 Correct 8 ms 2796 KB Output is correct
8 Correct 331 ms 8300 KB Output is correct
9 Correct 115 ms 8044 KB Output is correct
10 Correct 57 ms 4204 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 343 ms 8044 KB Output is correct
2 Correct 2 ms 2668 KB Output is correct
3 Correct 2 ms 2668 KB Output is correct
4 Correct 2 ms 2668 KB Output is correct
5 Correct 2 ms 2668 KB Output is correct
6 Correct 2 ms 2668 KB Output is correct
7 Correct 52 ms 3052 KB Output is correct
8 Correct 146 ms 2924 KB Output is correct
9 Correct 187 ms 8192 KB Output is correct
10 Correct 607 ms 10604 KB Output is correct
11 Correct 333 ms 8044 KB Output is correct
12 Correct 129 ms 7276 KB Output is correct
13 Correct 439 ms 10732 KB Output is correct
14 Correct 195 ms 7660 KB Output is correct
15 Correct 241 ms 6764 KB Output is correct
16 Correct 248 ms 6764 KB Output is correct

Subtask #3
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2668 KB Output is correct
2 Correct 2 ms 2668 KB Output is correct
3 Correct 3 ms 2668 KB Output is correct
4 Correct 2 ms 2668 KB Output is correct
5 Correct 2 ms 2668 KB Output is correct
6 Correct 3 ms 2796 KB Output is correct
7 Correct 4 ms 2796 KB Output is correct
8 Correct 6 ms 2924 KB Output is correct
9 Correct 5 ms 2924 KB Output is correct
10 Correct 39 ms 8044 KB Output is correct
11 Correct 77 ms 7788 KB Output is correct
12 Correct 167 ms 10092 KB Output is correct
13 Correct 134 ms 10860 KB Output is correct
14 Correct 99 ms 9068 KB Output is correct
15 Correct 75 ms 6636 KB Output is correct
16 Correct 73 ms 6636 KB Output is correct

Subtask #4
31.0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2668 KB Output is correct
2 Correct 2 ms 2668 KB Output is correct
3 Correct 3 ms 2668 KB Output is correct
4 Correct 2 ms 2668 KB Output is correct
5 Correct 2 ms 2668 KB Output is correct
6 Correct 3 ms 2796 KB Output is correct
7 Correct 4 ms 2796 KB Output is correct
8 Correct 6 ms 2924 KB Output is correct
9 Correct 5 ms 2924 KB Output is correct
10 Correct 39 ms 8044 KB Output is correct
11 Correct 77 ms 7788 KB Output is correct
12 Correct 167 ms 10092 KB Output is correct
13 Correct 134 ms 10860 KB Output is correct
14 Correct 99 ms 9068 KB Output is correct
15 Correct 75 ms 6636 KB Output is correct
16 Correct 73 ms 6636 KB Output is correct
17 Correct 208 ms 7996 KB Output is correct
18 Correct 2 ms 2668 KB Output is correct
19 Correct 2 ms 2668 KB Output is correct
20 Correct 2 ms 2668 KB Output is correct
21 Correct 2 ms 2668 KB Output is correct
22 Correct 2 ms 2668 KB Output is correct
23 Correct 27 ms 2892 KB Output is correct
24 Correct 38 ms 2924 KB Output is correct
25 Correct 46 ms 2924 KB Output is correct
26 Correct 44 ms 2924 KB Output is correct
27 Correct 104 ms 8044 KB Output is correct
28 Correct 400 ms 10476 KB Output is correct
29 Correct 488 ms 10988 KB Output is correct
30 Correct 336 ms 9196 KB Output is correct

Subtask #5
44.0 / 44.0

# Verdict Execution time Memory Grader output
1 Correct 379 ms 8300 KB Output is correct
2 Correct 2 ms 2668 KB Output is correct
3 Correct 2 ms 2668 KB Output is correct
4 Correct 2 ms 2668 KB Output is correct
5 Correct 8 ms 2796 KB Output is correct
6 Correct 7 ms 2796 KB Output is correct
7 Correct 8 ms 2796 KB Output is correct
8 Correct 331 ms 8300 KB Output is correct
9 Correct 115 ms 8044 KB Output is correct
10 Correct 57 ms 4204 KB Output is correct
11 Correct 343 ms 8044 KB Output is correct
12 Correct 2 ms 2668 KB Output is correct
13 Correct 2 ms 2668 KB Output is correct
14 Correct 2 ms 2668 KB Output is correct
15 Correct 2 ms 2668 KB Output is correct
16 Correct 2 ms 2668 KB Output is correct
17 Correct 52 ms 3052 KB Output is correct
18 Correct 146 ms 2924 KB Output is correct
19 Correct 187 ms 8192 KB Output is correct
20 Correct 607 ms 10604 KB Output is correct
21 Correct 333 ms 8044 KB Output is correct
22 Correct 129 ms 7276 KB Output is correct
23 Correct 439 ms 10732 KB Output is correct
24 Correct 195 ms 7660 KB Output is correct
25 Correct 241 ms 6764 KB Output is correct
26 Correct 248 ms 6764 KB Output is correct
27 Correct 2 ms 2668 KB Output is correct
28 Correct 2 ms 2668 KB Output is correct
29 Correct 3 ms 2668 KB Output is correct
30 Correct 2 ms 2668 KB Output is correct
31 Correct 2 ms 2668 KB Output is correct
32 Correct 3 ms 2796 KB Output is correct
33 Correct 4 ms 2796 KB Output is correct
34 Correct 6 ms 2924 KB Output is correct
35 Correct 5 ms 2924 KB Output is correct
36 Correct 39 ms 8044 KB Output is correct
37 Correct 77 ms 7788 KB Output is correct
38 Correct 167 ms 10092 KB Output is correct
39 Correct 134 ms 10860 KB Output is correct
40 Correct 99 ms 9068 KB Output is correct
41 Correct 75 ms 6636 KB Output is correct
42 Correct 73 ms 6636 KB Output is correct
43 Correct 208 ms 7996 KB Output is correct
44 Correct 2 ms 2668 KB Output is correct
45 Correct 2 ms 2668 KB Output is correct
46 Correct 2 ms 2668 KB Output is correct
47 Correct 2 ms 2668 KB Output is correct
48 Correct 2 ms 2668 KB Output is correct
49 Correct 27 ms 2892 KB Output is correct
50 Correct 38 ms 2924 KB Output is correct
51 Correct 46 ms 2924 KB Output is correct
52 Correct 44 ms 2924 KB Output is correct
53 Correct 104 ms 8044 KB Output is correct
54 Correct 400 ms 10476 KB Output is correct
55 Correct 488 ms 10988 KB Output is correct
56 Correct 336 ms 9196 KB Output is correct
57 Correct 1708 ms 11756 KB Output is correct
58 Correct 277 ms 8172 KB Output is correct
59 Correct 612 ms 8172 KB Output is correct