Submission #776204

#	Time	Username	Problem	Language	Result	Execution time	Memory
776204		canadavid1	Tropical Garden (IOI11_garden)	C++14	0 / 100	2 ms	340 KiB

garden

#include "garden.h"
#include "gardenlib.h"
#include <bits/stdc++.h>
using namespace std;
struct Node
{
  vector<Node*> n;
  int dtP=INT_MAX/2;
  bool dtPb;
  int dtP2=INT_MAX/2;
  bool dtP2b;
  int dtPf(Node *p)
  {
    if(p==n[0] && n.size()>1) return dtP2;
    return dtP;
  }
  bool dtPfb(Node *p)
  {
    if(p==n[0] && n.size()>1) return dtP2b;
    return dtPb;
  }
};
vector<Node> nodes;



int traverse_P(Node *t,Node* p,Node* P)
{
  static set<pair<Node*,bool>> seen;
  bool pwasmax = (t->n[0]==p);
  if(t==P) return 0;
  if(seen.count({t,pwasmax})) return INT_MAX/2;
  seen.insert({t,pwasmax});
  if(pwasmax && t->n.size()>1) return traverse_P(t->n[1],t,P)+1;
  else return traverse_P(t->n[0],t,P)+1;
}


void set_dtP(Node *t, Node *p,int dtP,bool dtPb)
{
  if(t->n[0]==p)
  {
    if((t->dtP)<(INT_MAX/4)) return;
    t->dtP = dtP;
    t->dtPb = dtPb;
    if(t->n.size()==1)
      set_dtP(t->n[0],t,dtP+1,dtPb);
    else for(int i = 1; i < t->n.size();i++)
      set_dtP(t->n[i],t,dtP+1,dtPb);
  }
  else if (t->n[1]==p)
  {
    if((t->dtP2)<(INT_MAX/4)) return;
    t->dtP2 = dtP;
    t->dtP2b = dtPb;
    set_dtP(t->n[0],t,dtP+1,dtPb);
  }
}

void count_routes(int N, int M, int P, int R[][2], int Q, int G[])
{
  // setup graph
  nodes.resize(N);
  for(int i = 0; i < M; i++)
  {
    nodes[R[i][0]].n.push_back(&nodes[R[i][1]]);
    nodes[R[i][1]].n.push_back(&nodes[R[i][0]]);
  }
  // traverse from P to P
  Node& Pn = nodes[P];
  for(int i = 1; i < Pn.n.size(); i++)
    set_dtP(Pn.n[i],&Pn,1,0);
  set_dtP(Pn.n[0],&Pn,1,1);
  Pn.dtP = Pn.n[0]->dtPf(&Pn)+1;
  Pn.dtPb = Pn.n[0]->dtPfb(&Pn);
  if(Pn.n.size()>1)
  {
    Pn.dtP2 = Pn.n[0]->dtPf(&Pn)+1;
    Pn.dtP2b = Pn.n[0]->dtPfb(&Pn);
  }

  array<vector<int>,2> dtP;
  dtP[0].assign(N,0);
  dtP[1].assign(N,0);
  

  for(auto i : nodes)
  {
    if(i.dtP < INT_MAX/4) dtP[i.dtPb][i.dtP]++;
  }
  dtP[0][0]++;
  for(int i = 0; i < Q; i++)
  {
    int num = G[i];
    int dtPv = num;
    bool dtPb = false;
    int c = 0;
    while(dtPv >= 0)
    {
      c += dtP[0][dtPv];
      if(dtPb)
      {
        dtPv -= Pn.dtP2;
        dtPb = Pn.dtP2b;
      }
      else
      {
        dtPv -= Pn.dtP;
        dtPb = Pn.dtPb;
      }
    }
    dtPv = num;
    dtPb = true;
    while(dtPv >= 0)
    {
      c += dtP[1][dtPv];
      if(dtPb)
      {
        dtPv -= Pn.dtP2;
        dtPb = Pn.dtP2b;
      }
      else
      {
        dtPv -= Pn.dtP;
        dtPb = Pn.dtPb;
      }
    }
    answer(c);
  }
  


  //for(i=0; i<N; i++) cout << i << " " << nodes[i].dtP << " " << nodes[i].dtP2 << "\n";
}



/* cases
    ==== work from first encounter of P
    either P0 -> P0
    or P0 -> P1
    or neither
    either P1 -> P0
    or P1 -> P1
    or neither

*/

Compilation message (stderr)

garden.cpp: In function 'void set_dtP(Node*, Node*, int, bool)':
garden.cpp:48:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Node*>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |     else for(int i = 1; i < t->n.size();i++)
      |                         ~~^~~~~~~~~~~~~
garden.cpp: In function 'void count_routes(int, int, int, int (*)[2], int, int*)':
garden.cpp:71:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Node*>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   71 |   for(int i = 1; i < Pn.n.size(); i++)
      |                  ~~^~~~~~~~~~~~~

• Subtask 1: 0 / 49
• Subtask 2: 0 / 20
• Subtask 3: 0 / 31