Submission #261320

# Submission time Handle Problem Language Result Execution time Memory
261320 2020-08-11T16:14:12 Z Nightlight Aesthetic (NOI20_aesthetic) C++14
100 / 100
1195 ms 70100 KB
#include <cstdio>
#include <queue>
#include <cstring>
#define pii pair<long long, int>
using namespace std;

int N, M;
vector<pii> adj[300005];
priority_queue<pii, vector<pii>, greater<pii>> pq;
long long dist[2][300005];
int U[300005], V[300005];
bool can[300005], ada[300005];
long long W[300005], best[300005];
vector<pair<int, int>> adj2[300005];
int disc[300005], low[300005], waktu, need;
bool ok;

void BFS(int id, int st) {
  memset(ada, 0, sizeof(ada));
  pq.emplace(0LL, st);
  dist[id][st] = 0;
  int u, v;
  long long len, w;
  while(!pq.empty()) {
    u = pq.top().second;
    len = pq.top().first;
    pq.pop();
    if(ada[u]) continue;
    ada[u] = 1;
    for(pii now : adj[u]) {
      v = now.second;
      w = now.first;
      if(dist[id][v] > len + w) {
        dist[id][v] = len + w;
        pq.emplace(dist[id][v], v);
      }
    }
  }
}

void DFS(int u, int p) {
  disc[u] = low[u] = ++waktu;
  int v, id;
  for(pair<int, int> now : adj2[u]) {
    id = now.second;
    if(ada[id] == 0) continue;
    v = now.first; 
    if(disc[v] <= need) {
      DFS(v, u);
      if(can[id] && low[v] > disc[u] && disc[N] >= disc[v] && disc[N] <= waktu) {
        ok = 1;
      }else low[u] = min(low[u], low[v]);
    }else if(p != v) {
      low[u] = min(low[u], disc[v]);
    }
  }
}

bool check(long long now) {
  ok = 0;
  need = waktu;
  for(int i = 1; i <= M; i++) {
    if(dist[0][U[i]] + W[i] + dist[1][V[i]] > now && dist[0][V[i]] + W[i] + dist[1][U[i]] > now) ada[i] = 0;
    else ada[i] = 1;
    if(dist[0][U[i]] + best[i] + W[i] + dist[1][V[i]] > now && dist[0][V[i]] + best[i] + W[i] + dist[1][U[i]] > now) can[i] = 1;
    else can[i] = 0;
  }
  DFS(1, 0);
  if(disc[N] <= need) return 1;
  if(ok) return 1;
  return 0;
}

int main() {
  memset(dist, 0x3f3f3f3f, sizeof(dist));
  scanf("%d %d", &N, &M);
  int u, v;
  long long w;
  for(int i = 1; i <= M; i++) {
    scanf("%d %d %lld", &u, &v, &w);
    U[i] = u, V[i] = v, W[i] = w;
    adj[u].emplace_back(w, v);
    adj[v].emplace_back(w, u);
    adj2[u].emplace_back(v, i);
    adj2[v].emplace_back(u, i);
  }
  for(int i = M - 1; i > 0; i--) {
    best[i] = max(best[i + 1], W[i + 1]);
  }
  BFS(0, 1);
  BFS(1, N);
  long long l = dist[0][N], r = dist[0][N] + best[1], res = dist[0][N], mid;
  while(l <= r) {
    mid = (l + r) >> 1;
    if(check(mid)) {
      l = mid + 1;
      res = l;
    }else r = mid - 1;
  }
  printf("%lld\n", res);
}

Compilation message

Aesthetic.cpp: In function 'int main()':
Aesthetic.cpp:76:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d", &N, &M);
   ~~~~~^~~~~~~~~~~~~~~~~
Aesthetic.cpp:80:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d %lld", &u, &v, &w);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 15 ms 19456 KB Output is correct
2 Correct 15 ms 19456 KB Output is correct
3 Correct 16 ms 19456 KB Output is correct
4 Correct 15 ms 19584 KB Output is correct
5 Correct 17 ms 19456 KB Output is correct
6 Correct 15 ms 19456 KB Output is correct
7 Correct 15 ms 19456 KB Output is correct
8 Correct 15 ms 19456 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 15 ms 19456 KB Output is correct
2 Correct 15 ms 19456 KB Output is correct
3 Correct 16 ms 19456 KB Output is correct
4 Correct 15 ms 19584 KB Output is correct
5 Correct 17 ms 19456 KB Output is correct
6 Correct 15 ms 19456 KB Output is correct
7 Correct 15 ms 19456 KB Output is correct
8 Correct 15 ms 19456 KB Output is correct
9 Correct 17 ms 19712 KB Output is correct
10 Correct 17 ms 19712 KB Output is correct
11 Correct 17 ms 19712 KB Output is correct
12 Correct 18 ms 19712 KB Output is correct
13 Correct 17 ms 19712 KB Output is correct
14 Correct 17 ms 19712 KB Output is correct
15 Correct 15 ms 19712 KB Output is correct
16 Correct 15 ms 19712 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 942 ms 56696 KB Output is correct
2 Correct 1079 ms 56628 KB Output is correct
3 Correct 997 ms 56568 KB Output is correct
4 Correct 943 ms 56440 KB Output is correct
5 Correct 1032 ms 56572 KB Output is correct
6 Correct 1075 ms 57592 KB Output is correct
7 Correct 1058 ms 57080 KB Output is correct
8 Correct 1037 ms 57592 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1134 ms 57420 KB Output is correct
2 Correct 1195 ms 56992 KB Output is correct
3 Correct 1172 ms 56056 KB Output is correct
4 Correct 1093 ms 56132 KB Output is correct
5 Correct 1071 ms 56700 KB Output is correct
6 Correct 1139 ms 56656 KB Output is correct
7 Correct 1061 ms 57080 KB Output is correct
8 Correct 1120 ms 57160 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 717 ms 54600 KB Output is correct
2 Correct 325 ms 52220 KB Output is correct
3 Correct 488 ms 58744 KB Output is correct
4 Correct 491 ms 58636 KB Output is correct
5 Correct 507 ms 58616 KB Output is correct
6 Correct 494 ms 58744 KB Output is correct
7 Correct 493 ms 58616 KB Output is correct
8 Correct 509 ms 58876 KB Output is correct
9 Correct 514 ms 58744 KB Output is correct
10 Correct 518 ms 59128 KB Output is correct
11 Correct 518 ms 58872 KB Output is correct
12 Correct 830 ms 54760 KB Output is correct
13 Correct 513 ms 58748 KB Output is correct
14 Correct 250 ms 69624 KB Output is correct
15 Correct 240 ms 69624 KB Output is correct
16 Correct 736 ms 55140 KB Output is correct
17 Correct 700 ms 54464 KB Output is correct
18 Correct 709 ms 54508 KB Output is correct
19 Correct 308 ms 52344 KB Output is correct
20 Correct 324 ms 52472 KB Output is correct
21 Correct 332 ms 52216 KB Output is correct
22 Correct 322 ms 52344 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 717 ms 54600 KB Output is correct
2 Correct 325 ms 52220 KB Output is correct
3 Correct 488 ms 58744 KB Output is correct
4 Correct 491 ms 58636 KB Output is correct
5 Correct 507 ms 58616 KB Output is correct
6 Correct 494 ms 58744 KB Output is correct
7 Correct 493 ms 58616 KB Output is correct
8 Correct 509 ms 58876 KB Output is correct
9 Correct 514 ms 58744 KB Output is correct
10 Correct 518 ms 59128 KB Output is correct
11 Correct 518 ms 58872 KB Output is correct
12 Correct 830 ms 54760 KB Output is correct
13 Correct 513 ms 58748 KB Output is correct
14 Correct 250 ms 69624 KB Output is correct
15 Correct 240 ms 69624 KB Output is correct
16 Correct 736 ms 55140 KB Output is correct
17 Correct 700 ms 54464 KB Output is correct
18 Correct 709 ms 54508 KB Output is correct
19 Correct 308 ms 52344 KB Output is correct
20 Correct 324 ms 52472 KB Output is correct
21 Correct 332 ms 52216 KB Output is correct
22 Correct 322 ms 52344 KB Output is correct
23 Correct 806 ms 56036 KB Output is correct
24 Correct 389 ms 52344 KB Output is correct
25 Correct 559 ms 54888 KB Output is correct
26 Correct 516 ms 54008 KB Output is correct
27 Correct 527 ms 54008 KB Output is correct
28 Correct 547 ms 55160 KB Output is correct
29 Correct 496 ms 54136 KB Output is correct
30 Correct 497 ms 54392 KB Output is correct
31 Correct 530 ms 54776 KB Output is correct
32 Correct 515 ms 54080 KB Output is correct
33 Correct 591 ms 54828 KB Output is correct
34 Correct 848 ms 55408 KB Output is correct
35 Correct 555 ms 54844 KB Output is correct
36 Correct 259 ms 70100 KB Output is correct
37 Correct 274 ms 70100 KB Output is correct
38 Correct 821 ms 55796 KB Output is correct
39 Correct 880 ms 55328 KB Output is correct
40 Correct 892 ms 56428 KB Output is correct
41 Correct 398 ms 52728 KB Output is correct
42 Correct 434 ms 52856 KB Output is correct
43 Correct 415 ms 52732 KB Output is correct
44 Correct 409 ms 52728 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 15 ms 19456 KB Output is correct
2 Correct 15 ms 19456 KB Output is correct
3 Correct 16 ms 19456 KB Output is correct
4 Correct 15 ms 19584 KB Output is correct
5 Correct 17 ms 19456 KB Output is correct
6 Correct 15 ms 19456 KB Output is correct
7 Correct 15 ms 19456 KB Output is correct
8 Correct 15 ms 19456 KB Output is correct
9 Correct 17 ms 19712 KB Output is correct
10 Correct 17 ms 19712 KB Output is correct
11 Correct 17 ms 19712 KB Output is correct
12 Correct 18 ms 19712 KB Output is correct
13 Correct 17 ms 19712 KB Output is correct
14 Correct 17 ms 19712 KB Output is correct
15 Correct 15 ms 19712 KB Output is correct
16 Correct 15 ms 19712 KB Output is correct
17 Correct 942 ms 56696 KB Output is correct
18 Correct 1079 ms 56628 KB Output is correct
19 Correct 997 ms 56568 KB Output is correct
20 Correct 943 ms 56440 KB Output is correct
21 Correct 1032 ms 56572 KB Output is correct
22 Correct 1075 ms 57592 KB Output is correct
23 Correct 1058 ms 57080 KB Output is correct
24 Correct 1037 ms 57592 KB Output is correct
25 Correct 1134 ms 57420 KB Output is correct
26 Correct 1195 ms 56992 KB Output is correct
27 Correct 1172 ms 56056 KB Output is correct
28 Correct 1093 ms 56132 KB Output is correct
29 Correct 1071 ms 56700 KB Output is correct
30 Correct 1139 ms 56656 KB Output is correct
31 Correct 1061 ms 57080 KB Output is correct
32 Correct 1120 ms 57160 KB Output is correct
33 Correct 717 ms 54600 KB Output is correct
34 Correct 325 ms 52220 KB Output is correct
35 Correct 488 ms 58744 KB Output is correct
36 Correct 491 ms 58636 KB Output is correct
37 Correct 507 ms 58616 KB Output is correct
38 Correct 494 ms 58744 KB Output is correct
39 Correct 493 ms 58616 KB Output is correct
40 Correct 509 ms 58876 KB Output is correct
41 Correct 514 ms 58744 KB Output is correct
42 Correct 518 ms 59128 KB Output is correct
43 Correct 518 ms 58872 KB Output is correct
44 Correct 830 ms 54760 KB Output is correct
45 Correct 513 ms 58748 KB Output is correct
46 Correct 250 ms 69624 KB Output is correct
47 Correct 240 ms 69624 KB Output is correct
48 Correct 736 ms 55140 KB Output is correct
49 Correct 700 ms 54464 KB Output is correct
50 Correct 709 ms 54508 KB Output is correct
51 Correct 308 ms 52344 KB Output is correct
52 Correct 324 ms 52472 KB Output is correct
53 Correct 332 ms 52216 KB Output is correct
54 Correct 322 ms 52344 KB Output is correct
55 Correct 806 ms 56036 KB Output is correct
56 Correct 389 ms 52344 KB Output is correct
57 Correct 559 ms 54888 KB Output is correct
58 Correct 516 ms 54008 KB Output is correct
59 Correct 527 ms 54008 KB Output is correct
60 Correct 547 ms 55160 KB Output is correct
61 Correct 496 ms 54136 KB Output is correct
62 Correct 497 ms 54392 KB Output is correct
63 Correct 530 ms 54776 KB Output is correct
64 Correct 515 ms 54080 KB Output is correct
65 Correct 591 ms 54828 KB Output is correct
66 Correct 848 ms 55408 KB Output is correct
67 Correct 555 ms 54844 KB Output is correct
68 Correct 259 ms 70100 KB Output is correct
69 Correct 274 ms 70100 KB Output is correct
70 Correct 821 ms 55796 KB Output is correct
71 Correct 880 ms 55328 KB Output is correct
72 Correct 892 ms 56428 KB Output is correct
73 Correct 398 ms 52728 KB Output is correct
74 Correct 434 ms 52856 KB Output is correct
75 Correct 415 ms 52732 KB Output is correct
76 Correct 409 ms 52728 KB Output is correct
77 Correct 986 ms 56576 KB Output is correct
78 Correct 693 ms 52856 KB Output is correct
79 Correct 715 ms 59000 KB Output is correct
80 Correct 710 ms 59128 KB Output is correct
81 Correct 700 ms 58832 KB Output is correct
82 Correct 696 ms 58824 KB Output is correct
83 Correct 718 ms 59196 KB Output is correct
84 Correct 641 ms 59364 KB Output is correct
85 Correct 637 ms 58872 KB Output is correct
86 Correct 730 ms 59008 KB Output is correct
87 Correct 730 ms 59084 KB Output is correct
88 Correct 996 ms 55468 KB Output is correct
89 Correct 722 ms 59044 KB Output is correct
90 Correct 389 ms 69968 KB Output is correct
91 Correct 394 ms 69876 KB Output is correct
92 Correct 975 ms 55848 KB Output is correct
93 Correct 950 ms 55432 KB Output is correct
94 Correct 911 ms 54892 KB Output is correct
95 Correct 717 ms 52472 KB Output is correct
96 Correct 659 ms 52612 KB Output is correct
97 Correct 705 ms 52600 KB Output is correct
98 Correct 692 ms 52264 KB Output is correct