Submission #997876

#	Time	Username	Problem	Language	Result	Execution time	Memory
997876		GrindMachine	Editor (BOI15_edi)	C++17	20 / 100	3051 ms	10064 KiB

edi

#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://github.com/dolphingarlic/CompetitiveProgramming/blob/master/Baltic/Baltic%2015-edi.cpp
https://oj.uz/submission/855227

*/

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; cin >> n;
    vector<ll> a(n+5);
    rep1(i,n) cin >> a[i];

    vector<ll> w(n+5);
    rep1(i,n){
        if(a[i] > 0){
            w[i] = 0;
        }
        else{
            w[i] = abs(a[i]);
        }
    }
 
    vector<ll> state(n+5); // 0 = undone, 1 = done
    state[0] = 1;
    vector<ll> par(n+5,-1);
 
    rep1(i,n){
        ll x = a[i];
        
        {
            ll j = i-1;
            while(j >= 0){
                if(w[i] > w[j]){
                    break;
                }
                j = par[j]-1;
            }

            amax(j,-1ll);
            par[i] = j;
        }

        // rev(j,i-1,0){
        //     if(state[j] and w[i] > w[j]){
        //         par[i] = j;
        //         break;
        //     }
        // }
    
        {
            ll j = i;
            while(j != -1){
                state[j] ^= 1;
                j = par[j];
            }
        }
        
        ll ans = -1;
        rep(j,i+1){
            if(state[j] and a[j] >= 0){
                ans = a[j];
            }
        }
 
        assert(ans != -1);
        cout << ans << endl;
    }
}

int main()
{
    fastio;

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

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

    return 0;
}

Compilation message (stderr)

edi.cpp: In function 'void solve(int)':
edi.cpp:83:12: warning: unused variable 'x' [-Wunused-variable]
   83 |         ll x = a[i];
      |            ^

• Subtask 1: 20 / 20
• Subtask 2: 0 / 15
• Subtask 3: 0 / 28
• Subtask 4: 0 / 37