Submission #819444

#	Time	Username	Problem	Language	Result	Execution time	Memory
819444		Alihan_8	Stations (IOI20_stations)	C++17	0 / 100	618 ms	768 KiB

stations

#include <bits/stdc++.h>

using namespace std;

#define all(x) x.begin(), x.end()
#define pb push_back
#define ln '\n'
//#define int long long

template <class _T>
bool chmin(_T &x, const _T &y){
    bool flag = false;
    if ( x > y ){
        x = y; flag |= true;
    }
    return flag;
}

template <class _T>
bool chmax(_T &x, const _T &y){
    bool flag = false;
    if ( x < y ){
        x = y; flag |= true;
    }
    return flag;
}

vector<int> label(int n, int k, vector<int> u, vector<int> v) {
    vector <int> ans(n);
    for ( int i = 0; i + 1 < n; i++ ){
        if ( u[i] > v[i] ) swap(u[i], v[i]);
        assert(u[i] == i / 2 && v[i] == i + 1);
    }
    for ( int i = 0; i < n; i++ ){
        ans[i] = i;
    }
    return ans;
}

int find_next_station(int s, int t, vector<int> c) {
    int bck = -1;
    auto in = [&](int s, int t){
        int x = __lg(s), y = __lg(t);
        if ( x >= y ){
            return false;
        }
        if ( s % 2 == 0 ){
            if ( (s + 1) * (1ll << y - x) <= t ){
                return false;
            }
        }
        if ( s & 1 ){
            if ( s * (1ll << y - x) > t ){
                return false;
            }
        }
        if ( (s * 2 + 1) * (1ll << y - x - 1) <= t ){
            bck = s * 2 + 1;
        } else bck = s * 2;
        return true;
    };
    auto flag = in(s + 1, t + 1);
    int res = flag ? bck - 1 : (s - 1) / 2;
    assert(binary_search(all(c), res));
    return in(s + 1, t + 1) ? bck - 1 : (s - 1) / 2;
}

Compilation message (stderr)

stations.cpp: In lambda function:
stations.cpp:48:38: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   48 |             if ( (s + 1) * (1ll << y - x) <= t ){
      |                                    ~~^~~
stations.cpp:53:32: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   53 |             if ( s * (1ll << y - x) > t ){
      |                              ~~^~~
stations.cpp:57:42: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   57 |         if ( (s * 2 + 1) * (1ll << y - x - 1) <= t ){
      |                                    ~~~~~~^~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 8
• Subtask 3: 0 / 16
• Subtask 4: 0 / 10
• Subtask 5: 0 / 61