Submission #1113020

#	Time	Username	Problem	Language	Result	Execution time	Memory
1113020		SalihSahin	Simurgh (IOI17_simurgh)	C++14	0 / 100	73 ms	3852 KiB

simurgh

#include <bits/stdc++.h>
#define pb push_back
#include "simurgh.h"

using namespace std;
/*
static int MAXQ = 30000;

static int n, m, q = 0;
static vector<int> u, v;
static vector<bool> goal;

static void wrong_answer() {
   printf("NO\n");
   exit(0);
}

static bool is_valid(const vector<int>& r) {
   if(int(r.size()) != n - 1)
      return false;

   for(int i = 0; i < n - 1; i++)
      if (r[i] < 0 || r[i] >= m)
         return false;

   return true;
}

static int _count_common_roads_internal(const vector<int>& r) {
   if(!is_valid(r))
      wrong_answer();

   int common = 0;
   for(int i = 0; i < n - 1; i++) {
      bool is_common = goal[r[i]];
      if (is_common)
         common++;
   }

   return common; 
}

int count_common_roads(const vector<int>& r) {
   q++;
   if(q > MAXQ)
      wrong_answer();

   return _count_common_roads_internal(r);
}
*/
const int MAXN = 5e2 + 5;
vector<int> par(MAXN);
vector<pair<int, int> > adj[MAXN];

int fnd(int a){
   if(a == par[a]) return a;
   return par[a] = fnd(par[a]);
}

void merge(int a, int b){
   a = fnd(a), b = fnd(b);
   par[b] = a;
}

vector<int> find_roads(int n, vector<int> u, vector<int> v) {
   vector<int> r;
   int m = u.size();
   vector<int> ok(m);
   for(int i = 0; i < m; i++){
      adj[u[i]].pb({v[i], i});
      adj[v[i]].pb({u[i], i});
   }

   for(int i = 0; i < n; i++){
      for(int j = 0; j < n; j++){
         par[j] = j;
      }
      vector<int> ottree;
      for(int j = 0; j < n; j++){
         if(j == i) continue;
         for(auto itr: adj[j]){
            if(itr.first == i) continue;
            if(fnd(j) == fnd(itr.first)) continue;
            ottree.pb(itr.second);
            merge(j, itr.first);
         }
      }
      if(ottree.size() == n-2){
         vector<pair<int, int> > vals;
         int mx = 0;
         for(auto itr: adj[i]){
            ottree.pb(itr.second);
            int cnt = count_common_roads(ottree);
            vals.pb({cnt, itr.second});
            mx = max(mx, cnt);
            ottree.pop_back();
         }
         for(auto itr: vals){
            if(itr.first == mx){
               ok[itr.second] = 1;
            }
         }
      }
   }

   for(int i = 0; i < m; i++){
      if(ok[i]) r.pb(i);
   }

   return r;
}
/*

int main() {
   assert(2 == scanf("%d %d", &n, &m));

   u.resize(m);
   v.resize(m);

   for(int i = 0; i < m; i++)
      assert(2 == scanf("%d %d", &u[i], &v[i]));

   goal.resize(m, false);

   for(int i = 0; i < n - 1; i++) {
      int id;
      assert(1 == scanf("%d", &id));
      goal[id] = true;
   }

   vector<int> res = find_roads(n, u, v);
   for(auto itr: res){
      cout<<itr<<" ";
   }
   cout<<endl;

   if(_count_common_roads_internal(res) != n - 1)
      wrong_answer();

   printf("YES\n");

   return 0;
}
*/

Compilation message (stderr)

simurgh.cpp: In function 'std::vector<int> find_roads(int, std::vector<int>, std::vector<int>)':
simurgh.cpp:88:24: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   88 |       if(ottree.size() == n-2){
      |          ~~~~~~~~~~~~~~^~~~~~

• Subtask 1: 0 / 13
• Subtask 2: 0 / 17
• Subtask 3: 0 / 21
• Subtask 4: 0 / 19
• Subtask 5: 0 / 30