Submission #283265

#	Time	Username	Problem	Language	Result	Execution time	Memory
283265		AlexLuchianov	Martian DNA (BOI18_dna)	C++14	100 / 100	176 ms	19832 KiB

dna

#include <iostream>
#include <vector>
#include <cassert>
#include <cmath>
#include <set>

using ll = long long;
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
#define MAX(a, b) (((a) < (b)) ? (b) : (a))

int const nmax = 200000;
std::vector<int> g[1 + nmax];
int ptr[1 + nmax], v[1 + nmax];
int cond[1 + nmax];

int main() {
  std::ios::sync_with_stdio(0);
  std::cin.tie(0);

  int n, k, q;
  std::cin >> n >> k >> q;
  for(int i = 1;i <= n; i++) {
    std::cin >> v[i];
    g[v[i]].push_back(i);
  }

  std::multiset<int> pq;
  for(int i = 1;i <= q;i++) {
    int val, cant;
    std::cin >> val >> cant;
    pq.insert(0);
    cond[val] = cant;
    if(g[val].size() < cant) {
      std::cout << "impossible";
      return 0;
    }
  }


  int result = n + 1;
  for(int i = 1;i <= n; i++) {
    ptr[v[i]]++;
    if(0 == cond[v[i]])
      continue;
    if(ptr[v[i]] == cond[v[i]]) {
      pq.erase(pq.find(0));
      pq.insert(g[v[i]][0]);
    } else if(cond[v[i]] < ptr[v[i]]) {
      pq.insert(g[v[i]][ptr[v[i]] - cond[v[i]] ]); 
      pq.erase(pq.find(g[v[i]][ptr[v[i]] - cond[v[i]] - 1]) );
    }
    if(0 < *pq.begin())
      result = std::min(result, i - *pq.begin() + 1);
  }

  if(result <= n)
    std::cout << result;
  else
    std::cout << "impossible";
  return 0;
}

Compilation message (stderr)

dna.cpp: In function 'int main()':
dna.cpp:33:22: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   33 |     if(g[val].size() < cant) {
      |        ~~~~~~~~~~~~~~^~~~~~

• Subtask 1: 16 / 16
• Subtask 2: 24 / 24
• Subtask 3: 28 / 28
• Subtask 4: 32 / 32