Submission #593833

# Submission time Handle Problem Language Result Execution time Memory
593833 2022-07-11T16:09:10 Z KrisjanisP Race (IOI11_race) C++14
100 / 100
499 ms 29228 KB
#include "race.h"
#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
using namespace std;
using ll = int;
using ii = pair<ll,ll>;

const ll MXN = 2e5;
const ll MXK = 1e6;

vector<ii> AL[MXN];
bool removed[MXN];

ll N, K;

ll subtreeSize[MXN];

// get size of a subtree
ll getSize(ll v, ll p)
{
  ll res = 1;
  for(auto& [u,w]: AL[v])
  {
    if(u==p) continue;
    if(removed[u]) continue;
    res += getSize(u,v);
  }
  subtreeSize[v] = res;
  return res;
}

// find the centroid
// of a connected component
ll findCentroid(ll v, ll p, ll n)
{
  bool found = true;
  ll sum = 1;
  for(auto& [u,w]: AL[v])
  {
    if(u==p) continue;
    if(removed[u]) continue;
    sum += subtreeSize[u];
    if(subtreeSize[u]>(n/2))
    {
      found = false;
      break;
    }
  }
  if((n-sum)>(n/2)) found = false;
  if(found) return v;
  for(auto& [u,w]: AL[v])
  {
    if(u==p) continue;
    if(removed[u]) continue;
    ll r = findCentroid(u,v,n);
    if(r!=-1) return r;
  }
  return -1;
}

// saves the depth at which was found
// the minimum depth and the second minimum
ll found[MXK+1];

void gather(ll v, ll p, ll d, ll s)
{
  if(s>K) return;
  if(found[s]==-1) found[s] = d;
  else found[s] = min(found[s],d);
  for(auto& [u,w]: AL[v])
  {
    if(u==p) continue;
    if(removed[u]) continue;
    gather(u,v,d+1,s+w);
  }
}

ll check(ll v, ll p, ll d, ll s)
{
  if(s>K) return -1;
  ll o = K-s;
  ll res = -1;
  if(found[o]!=-1) res = found[o]+d;
  for(auto& [u,w]: AL[v])
  {
    if(u==p) continue;
    if(removed[u]) continue;
    ll r = check(u,v,d+1,s+w);
    if(r!=-1)
    {
      if(res!=-1) res = min(res,r); 
      else res = r;
    }
  }
  return res;
}

void clear(ll v, ll p, ll s)
{
  if(s>K) return;
  found[s] = -1;
  for(auto& [u,w]: AL[v])
  {
    if(u==p) continue;
    if(removed[u]) continue;
    clear(u,v,s+w);
  }
}

// returns -1 or minimum highways
// such that v is included in the path
ll process(ll v)
{
  ll res = -1;
  for(auto& [u,w]: AL[v])
  {
    if(removed[u]) continue;
    found[0]=0;
    ll r = check(u,v,1,w);
    if(r!=-1)
    {
      if(res!=-1) res = min(res,r); 
      else res = r;
    }
    gather(u,v,1,w);
  }

  clear(v,v,0);

  return res;
}

// returns -1 or minimum highways
// in the whole connected component
// divide and conquer
ll DACE(ll v)
{
  ll sz = getSize(v,v);
  ll c = findCentroid(v,v,sz);
  ll res = process(c);
  removed[c] = 1;
  for(auto& [u,w]: AL[c])
  {
    if(removed[u]) continue;
    ll res_u = DACE(u);
    if(res_u!=-1){
      if(res==-1) res=res_u;
      else res=min(res, res_u);
    }
  }
  return res;
}

int best_path(int n, int k, int H[][2], int L[])
{
  N = n,K = k;
  for(ll i=1;i<=K;i++) found[i]=-1;
  for(ll i=0;i<N-1;i++)
  {
    ll a=H[i][0],b=H[i][1],w=L[i];
    AL[a].emplace_back(b,w);
    AL[b].emplace_back(a,w);
  }
  return DACE(0);
}

Compilation message

race.cpp: In function 'll getSize(ll, ll)':
race.cpp:22:13: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   22 |   for(auto& [u,w]: AL[v])
      |             ^
race.cpp: In function 'll findCentroid(ll, ll, ll)':
race.cpp:38:13: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   38 |   for(auto& [u,w]: AL[v])
      |             ^
race.cpp:51:13: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   51 |   for(auto& [u,w]: AL[v])
      |             ^
race.cpp: In function 'void gather(ll, ll, ll, ll)':
race.cpp:70:13: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   70 |   for(auto& [u,w]: AL[v])
      |             ^
race.cpp: In function 'll check(ll, ll, ll, ll)':
race.cpp:84:13: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   84 |   for(auto& [u,w]: AL[v])
      |             ^
race.cpp: In function 'void clear(ll, ll, ll)':
race.cpp:102:13: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  102 |   for(auto& [u,w]: AL[v])
      |             ^
race.cpp: In function 'll process(ll)':
race.cpp:115:13: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  115 |   for(auto& [u,w]: AL[v])
      |             ^
race.cpp: In function 'll DACE(ll)':
race.cpp:142:13: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  142 |   for(auto& [u,w]: AL[c])
      |             ^
# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 5076 KB Output is correct
3 Correct 3 ms 5000 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 2 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 3 ms 5004 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct
11 Correct 4 ms 5004 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 5004 KB Output is correct
15 Correct 3 ms 4932 KB Output is correct
16 Correct 3 ms 4948 KB Output is correct
17 Correct 3 ms 5012 KB Output is correct
18 Correct 3 ms 4948 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 5076 KB Output is correct
3 Correct 3 ms 5000 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 2 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 3 ms 5004 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct
11 Correct 4 ms 5004 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 5004 KB Output is correct
15 Correct 3 ms 4932 KB Output is correct
16 Correct 3 ms 4948 KB Output is correct
17 Correct 3 ms 5012 KB Output is correct
18 Correct 3 ms 4948 KB Output is correct
19 Correct 3 ms 4948 KB Output is correct
20 Correct 3 ms 4948 KB Output is correct
21 Correct 4 ms 5076 KB Output is correct
22 Correct 5 ms 8660 KB Output is correct
23 Correct 4 ms 8020 KB Output is correct
24 Correct 4 ms 8404 KB Output is correct
25 Correct 5 ms 8276 KB Output is correct
26 Correct 4 ms 6428 KB Output is correct
27 Correct 4 ms 8148 KB Output is correct
28 Correct 4 ms 5844 KB Output is correct
29 Correct 4 ms 6356 KB Output is correct
30 Correct 4 ms 6484 KB Output is correct
31 Correct 5 ms 7660 KB Output is correct
32 Correct 5 ms 7764 KB Output is correct
33 Correct 5 ms 8148 KB Output is correct
34 Correct 4 ms 7324 KB Output is correct
35 Correct 5 ms 8216 KB Output is correct
36 Correct 7 ms 8660 KB Output is correct
37 Correct 5 ms 8148 KB Output is correct
38 Correct 4 ms 6996 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 5076 KB Output is correct
3 Correct 3 ms 5000 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 2 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 3 ms 5004 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct
11 Correct 4 ms 5004 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 5004 KB Output is correct
15 Correct 3 ms 4932 KB Output is correct
16 Correct 3 ms 4948 KB Output is correct
17 Correct 3 ms 5012 KB Output is correct
18 Correct 3 ms 4948 KB Output is correct
19 Correct 133 ms 10884 KB Output is correct
20 Correct 133 ms 10916 KB Output is correct
21 Correct 139 ms 10908 KB Output is correct
22 Correct 128 ms 11024 KB Output is correct
23 Correct 69 ms 11248 KB Output is correct
24 Correct 52 ms 11076 KB Output is correct
25 Correct 135 ms 13356 KB Output is correct
26 Correct 92 ms 15052 KB Output is correct
27 Correct 165 ms 18812 KB Output is correct
28 Correct 242 ms 24912 KB Output is correct
29 Correct 214 ms 24428 KB Output is correct
30 Correct 170 ms 18892 KB Output is correct
31 Correct 178 ms 18768 KB Output is correct
32 Correct 185 ms 18860 KB Output is correct
33 Correct 220 ms 17556 KB Output is correct
34 Correct 168 ms 18476 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 5076 KB Output is correct
3 Correct 3 ms 5000 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 2 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 3 ms 5004 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct
11 Correct 4 ms 5004 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 5004 KB Output is correct
15 Correct 3 ms 4932 KB Output is correct
16 Correct 3 ms 4948 KB Output is correct
17 Correct 3 ms 5012 KB Output is correct
18 Correct 3 ms 4948 KB Output is correct
19 Correct 3 ms 4948 KB Output is correct
20 Correct 3 ms 4948 KB Output is correct
21 Correct 4 ms 5076 KB Output is correct
22 Correct 5 ms 8660 KB Output is correct
23 Correct 4 ms 8020 KB Output is correct
24 Correct 4 ms 8404 KB Output is correct
25 Correct 5 ms 8276 KB Output is correct
26 Correct 4 ms 6428 KB Output is correct
27 Correct 4 ms 8148 KB Output is correct
28 Correct 4 ms 5844 KB Output is correct
29 Correct 4 ms 6356 KB Output is correct
30 Correct 4 ms 6484 KB Output is correct
31 Correct 5 ms 7660 KB Output is correct
32 Correct 5 ms 7764 KB Output is correct
33 Correct 5 ms 8148 KB Output is correct
34 Correct 4 ms 7324 KB Output is correct
35 Correct 5 ms 8216 KB Output is correct
36 Correct 7 ms 8660 KB Output is correct
37 Correct 5 ms 8148 KB Output is correct
38 Correct 4 ms 6996 KB Output is correct
39 Correct 133 ms 10884 KB Output is correct
40 Correct 133 ms 10916 KB Output is correct
41 Correct 139 ms 10908 KB Output is correct
42 Correct 128 ms 11024 KB Output is correct
43 Correct 69 ms 11248 KB Output is correct
44 Correct 52 ms 11076 KB Output is correct
45 Correct 135 ms 13356 KB Output is correct
46 Correct 92 ms 15052 KB Output is correct
47 Correct 165 ms 18812 KB Output is correct
48 Correct 242 ms 24912 KB Output is correct
49 Correct 214 ms 24428 KB Output is correct
50 Correct 170 ms 18892 KB Output is correct
51 Correct 178 ms 18768 KB Output is correct
52 Correct 185 ms 18860 KB Output is correct
53 Correct 220 ms 17556 KB Output is correct
54 Correct 168 ms 18476 KB Output is correct
55 Correct 10 ms 5724 KB Output is correct
56 Correct 15 ms 5588 KB Output is correct
57 Correct 77 ms 11892 KB Output is correct
58 Correct 33 ms 11564 KB Output is correct
59 Correct 96 ms 15728 KB Output is correct
60 Correct 416 ms 29228 KB Output is correct
61 Correct 186 ms 18940 KB Output is correct
62 Correct 199 ms 22772 KB Output is correct
63 Correct 286 ms 22708 KB Output is correct
64 Correct 499 ms 21140 KB Output is correct
65 Correct 208 ms 19628 KB Output is correct
66 Correct 324 ms 27188 KB Output is correct
67 Correct 106 ms 23380 KB Output is correct
68 Correct 258 ms 23500 KB Output is correct
69 Correct 248 ms 23628 KB Output is correct
70 Correct 225 ms 22972 KB Output is correct