Submission #1069622

#	Time	Username	Problem	Language	Result	Execution time	Memory
1069622		GrindMachine	Tricks of the Trade (CEOI23_trade)	C++17	10 / 100	8089 ms	21372 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<ll,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
 
/*
 
refs:
https://codeforces.com/blog/entry/98663 (max+ convolution tutorial)
https://judge.yosupo.jp/submission/166484 (max+ convolution implementation) 
 
*/
 
const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

vector<pll> max_conv(vector<ll> a, vector<pll> b){
    // a = concave, b = arbitrary
    ll n = sz(a), m = sz(b);
    vector<pll> res(n+m-1,{-inf2,-inf2});
    rep(i,n){
        rep(j,m){
            amax(res[i+j],{b[j].ff+a[i],b[j].ss});
        }
    }

    return res;

    // vector<ll> res(n+m-1,-inf2);

    // auto go = [&](ll l, ll r, ll optl, ll optr, auto &&go) -> void{
    //     if(l > r) return;
    //     ll mid = (l+r) >> 1;
    //     ll best = -inf2, optm = -1;
    //     for(int j = optl; j <= optr; ++j){
    //         ll i = mid-j;
    //         if(i >= 0 and i < n){
    //             ll val = a[i]+b[j];
    //             if(val > best){
    //                 best = val;
    //                 optm = j;
    //             }
    //         }
    //     }

    //     res[mid] = best;
    //     go(l,mid-1,optl,optm,go);
    //     go(mid+1,r,optm,optr,go);
    // };

    // go(0,n+m-2,0,m-1,go);
    // return res;
}

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];    
 
    ll ans = -inf2;
    vector<pll> segs;

    auto upd = [&](ll l, ll r, ll v){
        if(v > ans){
            ans = v;
            segs.clear();
            segs.pb({l,r});
        }
        else if(v == ans){
            segs.pb({l,r});
        }
    };

    auto go = [&](ll l, ll r, auto &&go) -> pair<vector<pll>,vector<pll>>{
        if(l > r) return {{{0,0}},{{0,0}}};
        if(l == r){
            vector<pll> v = {{0,0},{-a[l]+b[l],1}};
            return {v,v};
        }
    
        ll mid = (l+r) >> 1;
        auto [lp,ls] = go(l,mid,go);
        auto [rp,rs] = go(mid+1,r,go);
        ll siz = r-l+1;
 
        vector<pll> cp(siz+1,{-inf2,-inf2}), cs(siz+1,{-inf2,-inf2});
        rep(i,sz(lp)) amax(cp[i],lp[i]);
        rep(i,sz(rs)) amax(cs[i],rs[i]);
 
        {
            vector<ll> vals;
            ll sum = 0;
            for(int i = l; i <= mid; ++i){
                sum -= a[i];
                vals.pb(b[i]);
            }
 
            sort(rall(vals));
            vals.insert(vals.begin(),sum);
            rep1(i,sz(vals)-1) vals[i] += vals[i-1];

            auto res = max_conv(vals,rp);
            rep(i,sz(res)) res[i].ss += mid-l+1;
            rep(i,sz(res)) amax(cp[i],res[i]);
        }
 
        {
            vector<ll> vals;
            ll sum = 0;
            for(int i = mid+1; i <= r; ++i){
                sum -= a[i];
                vals.pb(b[i]);
            }
 
            sort(rall(vals));
            vals.insert(vals.begin(),sum);
            rep1(i,sz(vals)-1) vals[i] += vals[i-1];

            auto res = max_conv(vals,ls);
            rep(i,sz(res)) res[i].ss += r-mid;
            rep(i,sz(res)) amax(cs[i],res[i]);
        }
 
        if(k < sz(cp)) upd(l,l+cp[k].ss-1,cp[k].ff);
        if(k < sz(cs)) upd(r-cs[k].ss+1,r,cs[k].ff);
 
        rep(j,sz(ls)){
            ll p = k-j;
            if(p >= 0 and p < sz(rp)){
                ll lx = mid-ls[j].ss+1;
                ll rx = mid+1+rp[p].ss-1;
                ll val = ls[j].ff+rp[p].ff;
                upd(mid-ls[j].ss+1,mid+1+rp[p].ss-1,ls[j].ff+rp[p].ff);
            }
        }
    
        rep1(i,sz(cp)-1) assert(cp[i].ss >= cp[i-1].ss);
        rep1(i,sz(cs)-1) assert(cs[i].ss >= cs[i-1].ss);

        return {cp,cs};
    };

    go(1,n,go);
    cout << ans << endl;
}
 
int main()
{
    fastio;
 
    int t = 1;
    // cin >> t;
 
    rep1(i, t) {
        solve(i);
    }
 
    return 0;
}

Compilation message (stderr)

trade.cpp: In instantiation of 'solve(int)::<lambda(ll, ll, auto:23&&)> [with auto:23 = solve(int)::<lambda(ll, ll, auto:23&&)>&; ll = long long int]':
trade.cpp:190:14:   required from here
trade.cpp:177:20: warning: unused variable 'lx' [-Wunused-variable]
  177 |                 ll lx = mid-ls[j].ss+1;
      |                    ^~
trade.cpp:178:20: warning: unused variable 'rx' [-Wunused-variable]
  178 |                 ll rx = mid+1+rp[p].ss-1;
      |                    ^~
trade.cpp:179:20: warning: unused variable 'val' [-Wunused-variable]
  179 |                 ll val = ls[j].ff+rp[p].ff;
      |                    ^~~

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