Submission #1144264

#	Time	Username	Problem	Language	Result	Execution time	Memory
1144264		Noproblem29	Seesaw (JOI22_seesaw)	C++20	100 / 100	170 ms	19300 KiB

seesaw

#include<bits/stdc++.h>
using namespace std;
#ifndef BADGNU
#pragma GCC target("sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
#endif
#pragma GCC optimize("Ofast,unroll-loops,fast-math,O3")
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp> 
using namespace __gnu_pbds;
#define ll long long
#define int ll
#define ld long double
#define y1 cheza
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
template<class T> using ordered_set = tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;
template<class T> using ordered_multiset = tree<T,null_type,less_equal<T>,rb_tree_tag,tree_order_statistics_node_update>;
const int N=2e5+100;
const int M=5001;
const int B=447;
const int mod=998244353;
const ll INF=1e18;
const int dx[]={1,-1,0,0};
const int dy[]={0,0,1,-1};
const double eps=1e-6;
int n;
int a[N];
int pref[N];
ld calc(int l,int r){
    return (pref[r]-pref[l-1])/((ld)(r-l+1));
}
ld ans=2e9;
void test(){
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>a[i];
        pref[i]=pref[i-1]+a[i];
    }
    set<tuple<ld,int,int>>s;
    int l=1;
    int r=n;
    ld mx=calc(1,n);
    while(1){
        s.insert({calc(l,r),l,r});
        if(l==r)break;
        if(calc(l+1,r)<=mx)l++;
        else r--;
    }
    while(1){
        auto [w,tl,tr]=*s.begin();
        s.erase(s.begin());
        ans=min(ans,mx-w);
        if(tr==n)break;
        s.insert({calc(tl+1,tr+1),tl+1,tr+1});
        mx=max(mx,calc(tl+1,tr+1));
    }   
    ld res=ans;
    cout<<fixed;
    cout<<setprecision(10);
    cout<<res<<'\n';
}



/*

*/
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    // cout.tie(nullptr);
    int t2=1;
    // cin>>t2;
    for(int i=1;i<=t2;i++){
        test();
    }
}

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