Submission #1144243

#	Time	Username	Problem	Language	Result	Execution time	Memory
1144243		Noproblem29	Seesaw (JOI22_seesaw)	C++20	1 / 100	2095 ms	324 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=2100;
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];
pair<int,int> dp[N][N];
bool operator<(const pair<int,int>&x,const pair<int,int>&y){
    return x.first*y.second<y.first*x.second;
}
bool operator<=(const pair<int,int>&x,const pair<int,int>&y){
    return x.first*y.second<=y.first*x.second;
}
bool operator>(const pair<int,int>&x,const pair<int,int>&y){
    return x.first*y.second>y.first*x.second;
}
bool operator>=(const pair<int,int>&x,const pair<int,int>&y){
    return x.first*y.second>=y.first*x.second;
}
bool operator==(const pair<int,int>&x,const pair<int,int>&y){
    return x.first*y.second==y.first*x.second;
}
pair<int,int>max(const pair<int,int>&x,const pair<int,int>&y){
    if(x<y){
        return y;
    }
    return x;
}

pair<int,int>min(const pair<int,int>&x,const pair<int,int>&y){
    if(x>y){
        return y;
    }
    return x;
}
pair<int,int>ans={1e9,1};
void dfs(int l,int r,pair<int,int>mx,pair<int,int>mn){
    mx=max(mx,make_pair(pref[r]-pref[l-1],(r-l+1)));
    mn=min(mn,make_pair(pref[r]-pref[l-1],(r-l+1)));
    if(l==r){
        pair<int,int>res={(mx.first*mn.second-mn.first*mx.second),(mx.second*mn.second)};
        ans=min(ans,res);
        return; 
    }
    dfs(l+1,r,mx,mn);
    dfs(l,r-1,mx,mn);
}
void test(){
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>a[i];
        pref[i]=pref[i-1]+a[i];
    }
    dfs(1,n,{pref[n],n},{pref[n],n});
    ld res=ans.first/((ld)ans.second);
    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: 0 / 33
• Subtask 3: 0 / 33
• Subtask 4: 0 / 33