Submission #1036798

#	Time	Username	Problem	Language	Result	Execution time	Memory
1036798		vjudge1	Abracadabra (CEOI22_abracadabra)	C++17	0 / 100	3071 ms	39068 KiB

Main

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define sort undefined_function // To use stable_sort instead sort 
#define bpc __builtin_popcount
#define ull unsigned long long
#define ld double
#define ll long long
#define mp make_pair
#define F first
#define S second

#pragma GCC optimize("O3")

#ifdef LOCAL 
        #include "debug.h"
#else 
        #define dbg(...) 0
#endif

using namespace __gnu_pbds;
using namespace std;

typedef tree<long long, null_type, less_equal<long long>,
    rb_tree_tag, tree_order_statistics_node_update> Tree;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const ll INF = 9223372036854775807LL;
const ll inf = 2147483647;
const ll MOD = 998244353; //[998244353, 1e9 + 7, 1e9 + 13]
const ld PI = acos(-1);
const ll NROOT = 800;

ll binpow(ll a, ll b, ll _MOD = -1) {
        if (_MOD == -1)
                _MOD = MOD;
        ll res = 1;
        for (; b; b /= 2, a *= a, a %= _MOD)
                if (b & 1) res *= a, res %= _MOD;
        return res;
}

void set_IO(string s) {
#ifndef LOCAL
        string in  = s +  ".in";
        string out = s + ".out";
        freopen(in.c_str(),  "r",  stdin);
        freopen(out.c_str(), "w", stdout);
#endif
}

bool dataOverflow(ll a, ll b) {return (log10(a) + log10(b) >= 18);}
ll gcd(ll a, ll b) {return b ? gcd(b, a % b) : a;}
ll lcm(ll a, ll b) {return a * b / gcd(a, b);}
ll ceil(ll a, ll b) {return (a + b - 1) / b;}
ll invmod(ll a) {return binpow(a, MOD - 2);}

int32_t main() {
        ios_base::sync_with_stdio(0);
        cin.tie(0);

        int n, q;
        cin >> n >> q;

        vector<int> v(n + 1);
        for (int i = 1; i <= n; i ++) 
                cin >> v[i];

        vector<pair<pair<int, int>, int>>qr(q + 1);

        for (int i = 1; i <= q; i ++) {
                cin >> qr[i].F.F >> qr[i].F.S;
                qr[i].S = i;
        }

        stable_sort(qr.begin() + 1, qr.end());
        vector<int> ans(q + 1, -1);

        int iter = 1;
        for (int i = 0; iter < qr.size(); i ++) {
                while (iter < qr.size() && qr[iter].F.F == i) {
                        ans[qr[iter].S] = v[qr[iter].F.S];
                        iter ++;
                }

                vector<int> half1, half2;
                for (int j = 1; j <= n / 2; j ++) 
                       half1.push_back(v[j]);
                for (int j = n / 2 + 1; j <= n; j ++) 
                       half2.push_back(v[j]);

                reverse(half1.begin(), half1.end());
                reverse(half2.begin(), half2.end());

                int tmp = 1;
                while (!half1.empty() && !half2.empty()) {
                        if (half1.back() < half2.back()) {
                                v[tmp] = half1.back();
                                half1.pop_back();
                        } else {
                                v[tmp] = half2.back();
                                half2.pop_back();
                        }

                        tmp ++;
                }

                while (!half1.empty()) {
                        v[tmp] = half1.back();
                        half1.pop_back();
                        tmp ++;
                }
                while (!half2.empty()) {
                        v[tmp] = half2.back();
                        half2.pop_back();
                        tmp ++;
                }

                if (is_sorted(v.begin() + 1, v.end())) 
                        break;
        }

        for (int i = 1; i <= n; i ++) 
                if (ans[qr[i].S] == -1) 
                        ans[qr[i].S] = v[qr[i].F.S];

        for (int i = 1; i <= q; i ++) {
                cout << ans[i] << "\n";
        }

        return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int32_t main()':
Main.cpp:80:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<int, int>, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   80 |         for (int i = 0; iter < qr.size(); i ++) {
      |                         ~~~~~^~~~~~~~~~~
Main.cpp:81:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<int, int>, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   81 |                 while (iter < qr.size() && qr[iter].F.F == i) {
      |                        ~~~~~^~~~~~~~~~~
Main.cpp: In function 'void set_IO(std::string)':
Main.cpp:47:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |         freopen(in.c_str(),  "r",  stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:48:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |         freopen(out.c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 40
• Subtask 3: 0 / 25
• Subtask 4: 0 / 25