Submission #479518

#	Time	Username	Problem	Language	Result	Execution time	Memory
479518		kamalsharmaa9	Race (IOI11_race)	C++14	9 / 100	393 ms	54072 KiB

race

//https://pastebin.com/jVURaNCJ
#include<bits/stdc++.h>
#include <cstdio>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;

#define N              200005
#define ff              first
#define ss              second
#define int             long long
#define pb              push_back
#define mp              make_pair
#define pii             pair<int,int>
#define vi              vector<int>
#define mii             map<int,int>
#define pqb             priority_queue<int>
#define pqs             priority_queue<int,vi,greater<int> >
#define setbits(x)      __builtin_popcountll(x)
#define zrobits(x)      __builtin_ctzll(x)
#define mod             1000000007
#define inf             1e18
#define ps(x,y)         fixed<<setprecision(y)<<x
#define mk(arr,n,type)  type *arr=new type[n];
#define w(x)            int x; cin>>x; while(x--)
mt19937                 rng(chrono::steady_clock::now().time_since_epoch().count());

typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> pbds;


void c_p_c()
{
  ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);


}
vector<int>gr[N];
map<int, map<int, int>>edge;
map<int, int>m[N];
int depth[N];
int fin_ans = inf;
int val[N];
int k;
int dfs1(int node, int par)
{

  int ans = 0;
  for (auto child : gr[node])
  {
    if (child != par)
    {
      ans = max(ans, dfs1(child, node) + 1);
    }
  }

  return depth[node] = ans;
}
int dfs(int node, int par)
{

  ///cout << node << "++";
  int sz = 0;
  int ind;
  for (auto child : gr[node])
  {
    // cout << child << endl;
    if (child != par )
    {
      //cout << child << endl;
      int temp = dfs(child, node);
      if (temp > sz)
      {
        sz = temp;
        ind = child;
      }
    }
  }
  if (sz == 0) {
    val[node] = 0;
    m[node][0] = 0;
    return 1;
  }

  for (auto child : gr[node])
  {
    if (child == par)
      continue;
    int to_find = k - edge[node][child];
    //cout << "to_find" << to_find << endl;
    if (to_find == 0)
      fin_ans = 1;
    to_find = to_find - val[child];
    if (m[child].find(to_find) != m[child].end())
    {
      //cout << "came" << endl;

      fin_ans = min(fin_ans, 1 + depth[child] - m[child][to_find]);
    }
  }
  m[node].swap(m[ind]);
  val[node] = val[ind] + edge[node][ind];
  m[node][edge[node][ind] - val[node]] = depth[node] - 1;
  ////////////////////////////////alll deal with child to node
  // and inserted bigger_child and done with that
  for (auto child : gr[node])
  {
    if (child != par && child != ind)
    {
      // go in this
      for (auto i : m[child])
      {
        int num = i.ff + val[child] + edge[node][child];
        int to_find = k - num - val[node];
        if (m[node].find(to_find) != m[node].end())
        {
          //  cout << "came" << endl;

          fin_ans = min(fin_ans, depth[node] - m[node][to_find] + depth[child] - i.ss + 1);
        }
      }
      int findd = k - edge[node][child];
      if (m[node].find(findd) != m[node].end())
      {
        //
        // cout << "came" << endl;
        fin_ans = min(fin_ans, depth[node] - m[node][findd] + 1);
      }
      for (auto i : m[child])
      {
        int num = i.ff + val[child];
        int to_insert = num - val[node];
        int d = i.ss;
        int newd = depth[node] - 1 - (depth[child] - i.ss);
        if (m[node].find(to_insert) != m[node].end())
        {
          if (m[node][to_insert] < newd)
            m[node][to_insert] = newd;
        }
        else
          m[node][to_insert] = newd;

      }
      m[node][edge[node][child] - val[node]] = depth[node] - 1;
    }
  }
  //cout << node << " " << val[node] << " " << depth[node] << " " << fin_ans << endl;
  return m[node].size();
}

int best_path(int32_t n, int32_t K, int32_t H[][2], int32_t L[]) {
  int i, j, a, b, c;
  //scanf("%lld%lld",&n,&l);
  k = K;
  for (int i = 0; i <= n; i++)
  {
    gr[i].clear();
    m[i].clear();
    depth[i] = 0;
  }
  fin_ans = inf;
  edge.clear();
  for (i = 0; i < n - 1; i++) {
    //scanf("%lld%lld%lld",&a,&b,&c);
    //a++;b++;
    a = H[i][0]; b = H[i][1]; c = L[i];
    a++; b++;
    //cout << a << b << c << endl;
    edge[a][b] = c;
    edge[b][a] = c;
    gr[a].pb(b);
    gr[b].pb(a);
  }
  dfs1(1, 0);
  dfs(1, 0);
  if (fin_ans == inf)
    return -1;
  return (int32_t)fin_ans;

}

Compilation message (stderr)

race.cpp: In function 'long long int dfs(long long int, long long int)':
race.cpp:132:13: warning: unused variable 'd' [-Wunused-variable]
  132 |         int d = i.ss;
      |             ^
race.cpp: In function 'long long int best_path(int32_t, int32_t, int32_t (*)[2], int32_t*)':
race.cpp:151:10: warning: unused variable 'j' [-Wunused-variable]
  151 |   int i, j, a, b, c;
      |          ^

• Subtask 1: 9 / 9
• Subtask 2: 0 / 12
• Subtask 3: 0 / 22
• Subtask 4: 0 / 57