Submission #743383

#	Time	Username	Problem	Language	Result	Execution time	Memory
743383		Cookie	Bitaro's travel (JOI23_travel)	C++14	0 / 100	0 ms	340 KiB

travel

#include<bits/stdc++.h>
#include<fstream>
using namespace std;
ifstream fin("VNOICUP.INP");
ofstream fout("VNOICUP.OUT");
#define sz(a) (int)a.size()
#define ll long long
#define pb push_back
#define forr(i, a, b) for(int i = a; i < b; i++)
#define dorr(i, a, b) for(int i = a; i >= b; i--)
#define ld long double
#define vt vector
#include<fstream>
#define fi first
#define se second
#define pll pair<ll, ll>
#define pii pair<int, int>
const ld PI = 3.14159265359;
const int x[4] = {1, -1, 0, 0};
const int y[4] = {0, 0, 1, -1};
const ll mod = 1e9 + 7;
const int mxn = 1e6 + 5, mxm = 1e5, sq = 400;
const int base = (1 << 18);
const int inf = 1e9, neg = -69420;
int n, q;
int up[mxn + 1][18], a[mxn + 1];
int get(int l, int r){
    int lg = __lg(r - l + 1);
    return(max(up[l][lg], up[r - (1 << lg) + 1][lg]));
}
void solve(){
    int s; cin >> s;
    int l = lower_bound(a + 1, a + n + 1, s) - a - 1;
    if(l == 0){
        cout << a[n] - s << "\n";
        return;
    }
    int r = lower_bound(a + 1, a + n + 1, s) - a;
    if(r == n || r == n + 1){
        cout << s - a[1] << "\n";
        return;
    }
    ll res = 0, pos = s;
    bool dir;
    if(a[r] - s < s - a[l]){
        dir = 1; l = r;
    }else{
        dir = 0; r = l;
    }
    
    
    vt<pii>path;
    while(l != 1 && r != n){
        if(dir){
            int le = r + 1, ri = n, ans = r;
            while(le <= ri){
                int mid = (le + ri) >> 1;
                if(get(r, mid - 1) < a[r] - a[l - 1]){
                    ans = mid; le = mid + 1;
                }else{
                    ri = mid - 1;
                }
            }
            path.pb({pos, a[ans]}); path.pb({a[ans], a[l - 1]}); r = ans; l--; pos = a[l];
        }else{
            int le = 1, ri = l - 1, ans = l;
            while(le <= ri){
                int mid = (le + ri) >> 1;
                if(get(mid, l - 1) <= a[r + 1] - a[l]){
                    ans = mid; ri = mid - 1;
                }else{
                    le = mid + 1;
                }
            }
            path.pb({pos, a[ans]}); path.pb({a[ans], a[r + 1]}); l = ans; r++; pos = a[r];
        }
        //cout << l << " " <<  r << "\n";
        dir = !dir;
        
    }
    
    if(!dir){
        path.pb({a[l], a[n]});
    }if(dir){
        path.pb({a[n], a[r]});
    }
    for(auto [u, v]: path){
        res += abs(u - v);
    }
    cout << res << "\n";
    /*
    //cout << cnt << ' ';
    if(l != 1){
       // assert(dir == 0 && r == n + 1);
        res += a[n] - a[1];
    }if(r != n){
        //assert(dir == 1 && l == 0);
        res += a[n] - a[r];
    }
    */
    
}
signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin >> n;
    forr(i, 1, n + 1)cin >> a[i];
    forr(i, 1, n){
        up[i][0] = a[i + 1] - a[i];
    }
    for(int i = 1; i < 18; i++){
        for(int j = 1; j + (1 << i) - 1 < n; j++){
            up[j][i] = max(up[j][i - 1], up[j + (1 << (i - 1))][i - 1]);
        }
    }
    cin >> q;
    forr(i, 0, q){
        solve();
        
    }
    return(0);
}

Compilation message (stderr)

travel.cpp: In function 'void solve()':
travel.cpp:87:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   87 |     for(auto [u, v]: path){
      |              ^

• Subtask 1: 0 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 30
• Subtask 4: 0 / 55