Submission #1072257

#	Time	Username	Problem	Language	Result	Execution time	Memory
1072257		duckindog	Art Collections (BOI22_art)	C++17	35 / 100	119 ms	596 KiB

art

#include <bits/stdc++.h>

#ifndef LOCAL
#include "art.h"
#endif

using namespace std;

void __attribute__((noreturn)) __attribute__((format(printf, 1, 2))) result(const char *msg, ...) {
    va_list args;
    va_start(args, msg);
    vfprintf(stdout, msg, args);
    fprintf(stdout, "\n");
    va_end(args);
    exit(0);
}

#ifdef LOCAL
namespace {
    int N;
    int Q = 0;
    const int MAX_Q = 4000;
    const int MAX_N = 4000;
    vector<int> solution;
}  // namespace

int publish(vector<int> R) {
    printf("publish({");
    for(int i = 0; i < int(R.size()); ++i) {
        if(i == 0)
            printf("%d", R[i]);
        else
            printf(", %d", R[i]);
    }
    printf("})\n");
    fflush(stdout);

    if (++Q > MAX_Q)
        result("Too many published rankings!");

    if (int(R.size()) != N)
        result("Invalid published ranking!");

    set<int> chosen;
    for(auto &x : R) {
        if(x < 1 || x > N || chosen.count(x))
            result("Invalid published ranking!");
        chosen.insert(x);
    }
    vector<int> positions(N+1);
    for(int i = 0; i < N; ++i)
        positions[R[i]] = i;

    int complaints = 0;
    for(int i = 0; i < N; ++i) {
        for(int j = i+1; j < N; ++j) {
            if(positions[solution[i]] > positions[solution[j]])
                ++complaints;
        }
    }

    return complaints;
}

void __attribute__((noreturn)) answer(vector<int> R) {
    printf("answer({");
    for(int i = 0; i < int(R.size()); ++i) {
        if(i == 0)
            printf("%d", R[i]);
        else
            printf(", %d", R[i]);
    }
    printf("})\n");
    fflush(stdout);


    if(R == solution)
        result("Correct: %d published ranking(s).", Q);
    else
        result("Wrong answer!");
}
#endif

void solve(int n) {
  vector<int> vt(n); iota(vt.begin(), vt.end(), 1);

  for (int i = 1; i < n; ++i) { 
    int x = vt.end()[-1 - i];
    vt.erase(vt.end() - i - 1, vt.end() - i);

    vector<int> fast(n + 1);

    auto chk = [&](int p) { 
      if (fast[p]) return fast[p];

      vt.insert(vt.end() - p, x);
      int ret = publish(vt);
      if (!ret) { answer(vt); exit(0); }

      vt.erase(vt.end() - p - 1, vt.end() - p);
      return fast[p] = ret;
    };

    int l = 0, r = i - 1, it = 0;
    while (l <= r) { 
      int mid = l + r >> 1;
      if (chk(mid) > chk(mid + 1)) l = it = mid + 1;
      else r = mid - 1;
    }

    vt.insert(vt.end() - it, x);
  }
  answer(vt);
}

#ifdef LOCAL
int main() {
    if (scanf("%d", &N) != 1 || N < 2 || N > MAX_N)
        result("Invalid input!");

    solution.resize(N);
    set<int> chosen;
    for(auto &x : solution) {
        if(scanf("%d", &x) != 1 || x < 1 || x > N || chosen.count(x))
            result("Invalid input!");
        chosen.insert(x);
    }

    solve(N);

    result("No answer!");
}
#endif

Compilation message (stderr)

art.cpp: In function 'void solve(int)':
art.cpp:106:19: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  106 |       int mid = l + r >> 1;
      |                 ~~^~~
interface.cpp: In function 'int publish(std::vector<int>)':
interface.cpp:20:17: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   20 |     if(v.size() != N) {
      |        ~~~~~~~~~^~~~
interface.cpp: In function 'void answer(std::vector<int>)':
interface.cpp:36:17: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   36 |     if(v.size() != N) {
      |        ~~~~~~~~~^~~~

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3: 15 / 15
• Subtask 4: 0 / 15
• Subtask 5: 0 / 20
• Subtask 6: 0 / 30