Submission #635780

#	Time	Username	Problem	Language	Result	Execution time	Memory
635780		Dec0Dedd	CONSUL (info1cup19_consul)	C++14	100 / 100	61 ms	208 KiB

consul

#include <bits/stdc++.h>
#include "grader.h"

using namespace std;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

int rnd(int a, int b){ 
	return a+rng()%(b-a+1);
}

void solve(int n) {
   pair<int, int> x={0, -1};

   vector<int> v;
   for (int i=1; i<=n; ++i) v.push_back(i);
   shuffle(v.begin(), v.end(), rng);

   if (n <= 50) {
      map<int, int> cnt;
      for (int i=1; i<=n; ++i) {
         int val=kth(i);
         ++cnt[val];

         if (cnt[val] > n/3) {
            say_answer(val);
            return;
         }
      }

      say_answer(-1);
      return;
   }

   for (int i=0; i<min(n, 30); ++i) {
      int r=v[i], val=kth(r);
      x=max(x, {cnt(val), val});
   }
   if (x.first > n/3) say_answer(x.second);
   else say_answer(-1); 
}

• Subtask 1: 15 / 15
• Subtask 2: 20 / 20
• Subtask 3: 65 / 65