Submission #1069547

#	Time	Username	Problem	Language	Result	Execution time	Memory
1069547		GrindMachine	Tricks of the Trade (CEOI23_trade)	C++17	0 / 100	909 ms	39508 KiB

trade

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ld,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif

/*



*/

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

void solve(int test_case)
{
    ll n,k; cin >> n >> k;
    vector<ll> a(n+5), b(n+5);
    rep1(i,n) cin >> a[i];
    rep1(i,n) cin >> b[i];    

    vector<pll> dp(n+5,{-1,-1});

    auto go = [&](ll i, ld lambda, auto &&go) -> pll{
        if(i > n) return {0,0};
        if(dp[i].ss != -1) return dp[i];

        auto p1 = go(i+1,lambda,go), p2 = go(i+1,lambda,go);
        p1.ff += -a[i];
        p2.ff += -a[i]+b[i]-lambda;
        auto px = p1;

        if(p2.ff >= p1.ff){
            px = p2;
            px.ss++;
        }

        return dp[i] = px;
    };

    auto get = [&](ld lambda){
        fill(all(dp),pll{-1,-1});
        pll ans = {0,0};
        rep1(i,n){
            amax(ans,go(i,lambda,go));
        }
        return ans;
    };

    ld lo = -inf1, hi = inf1;
    ld lambda = inf1+1;

    rep(iter,100){
        ld mid = (lo+hi)/2;
        auto [cost,cnt] = get(mid);
        if(cnt <= k){
            amin(lambda,mid);
            hi = mid;
        }
        else{
            lo = mid;
        }
    }

    auto [cost,cnt] = get(lambda);
    ll ans = round(cost+lambda*cnt);
    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

• Subtask 0: 0 / 0
• Subtask 1: 0 / 10
• Subtask 2: 0 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 25
• Subtask 5: 0 / 45