Submission #910952

#	Time	Username	Problem	Language	Result	Execution time	Memory
910952		cig32	Seesaw (JOI22_seesaw)	C++17	100 / 100	382 ms	74044 KiB

seesaw

#include "bits/stdc++.h"
using namespace std;
#define int long long
#define double long double
const int MAXN = 2e5 + 10;
const int MOD = 1e9 + 7;
mt19937_64 rng((int)std::chrono::steady_clock::now().time_since_epoch().count());
int rnd(int x, int y) {
  int u = uniform_int_distribution<int>(x, y)(rng); return u;
}
int bm(int b, int p) {
  if(p==0) return 1 % MOD;
  int r = bm(b, p >> 1);
  if(p&1) return (((r*r) % MOD) * b) % MOD;
  return (r*r) % MOD;
}
int inv(int b) { 
  return bm(b, MOD-2);
}
int fastlog(int x) {
  return (x == 0 ? -1 : 64 - __builtin_clzll(x) - 1);
}
void printcase(int i) { cout << "Case #" << i << ": "; }
static void run_with_stack_size(void (*func)(void), size_t stsize) {
  char *stack, *send;
  stack = (char *)malloc(stsize);
  send = stack + stsize - 16;
  send = (char *)((uintptr_t)send / 16 * 16);
  asm volatile(
    "mov %%rsp, (%0)\n"
    "mov %0, %%rsp\n"
    :
    : "r"(send));
  func();
  asm volatile("mov (%0), %%rsp\n" : : "r"(send));
  free(stack);
}
void solve(int tc) { 
  int n;
  cin >> n;
  int a[n+1];
  for(int i=1; i<=n; i++) {
    cin >> a[i];
  }
  sort(a+1, a+n+1);
  int ps[n+1];
  ps[0] = 0;
  for(int i=1; i<=n; i++) ps[i] = ps[i-1] + a[i];
  vector<pair<double,int>>v;
  for(int len=1; len<=n; len++) {
    int lb = 1, rb = n-len+1;
    while(lb < rb) {
      int mid = (lb + rb) >> 1;
      double bruh = (ps[mid+len-1] - ps[mid-1]) * 1.0 / len;
      if(bruh >= ps[n] * 1.0 / n) rb = mid;
      else lb = mid + 1;
    }
    for(int j=max(1ll, lb - 4); j<=min(n-len+1, lb + 4); j++) {
      double bruh = (ps[j+len-1] - ps[j-1]) * 1.0 / len;
      v.push_back({bruh, len});
    }
  }
  sort(v.begin(), v.end());
  int freq[n+1];
  for(int i=1; i<=n; i++) freq[i] = 0;
  int s = 0, j = -1;
  double ans = 1e9;
  for(int i=0; i<v.size(); i++) {
    if(i > 0) {
      int bruh = v[i-1].second;
      freq[bruh]--;
      if(!freq[bruh]) s--;
    }
    j = max(j, i-1);
    while(s < n && j+1 < v.size()) {
      j++;
      int bruh = v[j].second;
      freq[bruh]++;
      if(freq[bruh] == 1) s++;
    }
    if(s == n) ans = min(ans, v[j].first - v[i].first);
  }
  cout << fixed << setprecision(10) << ans << '\n';
}

void uwu() {
  ios::sync_with_stdio(0); cin.tie(0);
  int t = 1; //cin >> t;
  for(int i=1; i<=t; i++) solve(i);
}
int32_t main() {
  #ifdef ONLINE_JUDGE
  uwu();
  #endif
  #ifndef ONLINE_JUDGE
  run_with_stack_size(uwu, 1024 * 1024 * 1024); // run with a 1 GiB stack
  #endif
}
/*
g++ A.cpp -std=c++17 -O2 -o A
./A < input.txt
*/

Compilation message (stderr)

seesaw.cpp: In function 'void solve(long long int)':
seesaw.cpp:68:17: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long double, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   68 |   for(int i=0; i<v.size(); i++) {
      |                ~^~~~~~~~~
seesaw.cpp:75:24: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long double, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   75 |     while(s < n && j+1 < v.size()) {
      |                    ~~~~^~~~~~~~~~

• Subtask 1: 1 / 1
• Subtask 2: 33 / 33
• Subtask 3: 33 / 33
• Subtask 4: 33 / 33