Submission #1172456

#	Time	Username	Problem	Language	Result	Execution time	Memory
1172456		Zero_OP	Bitaro's travel (JOI23_travel)	C++20	100 / 100	152 ms	31956 KiB

travel

#include <bits/stdc++.h>

using namespace std;

#define FOR(i, l, r) for(int i = (l); i < (r); ++i)
#define ROF(i, r, l) for(int i = (r)-1; i >= (l); --i)

#define mp make_pair
#define mt make_tuple
#define ff first
#define ss second

#define all(v) begin(v), end(v)
#define rall(v) rbegin(v), rend(v)
#define sz(v) (int)v.size()
#define pb push_back
#define eb emplace_back
#define compact(v) v.erase(unique(all(v)), end(v))

#define dbg(x) "[" #x " = " << (x) << "]"

template<typename T>
      bool minimize(T& a, const T& b){
            if(a > b) return a = b, true;
            return false;
      }

template<typename T>
      bool maximize(T& a, const T& b){
            if(a < b) return a = b, true;
            return false;
      }

typedef long long ll;

using db = double;
using ull = unsigned long long;

using pi = pair<int, int>;
using pl = pair<ll, ll>;
using pd = pair<db, db>;

using vi = vector<int>;
using vl = vector<ll>;
using vc = vector<char>;
using vd = vector<db>;
using vb = vector<bool>;

using vpi = vector<pi>;
using vpl = vector<pl>;

void setIO(){
      ios_base::sync_with_stdio(0); cin.tie(0);
#ifdef LOCAL
      freopen("task.inp", "r", stdin);
      freopen("task.out", "w", stdout);
#endif
}


struct MinSPT{
      vector<vi> rmq;
      MinSPT(vi ar) : rmq(){
            rmq.pb(ar);
            for(int i = 1; (1 << i) <= sz(ar); ++i){
                  rmq.pb(vi(sz(ar) - (1 << i) + 1));
                  for(int j = 0; j + (1 << i) <= sz(ar); ++j){
                        rmq[i][j] = min(rmq[i-1][j], rmq[i-1][j + (1 << (i-1))]);
                  }
            }
      }

      int query(int l, int r){
            int k = 31 - __builtin_clz(r - l + 1);
            return min(rmq[k][l], rmq[k][r - (1 << k) + 1]);
      }
};

struct MaxSPT{
      vector<vi> rmq;
      MaxSPT(vi ar) : rmq(){
            rmq.pb(ar);
            for(int i = 1; (1 << i) <= sz(ar); ++i){
                  rmq.pb(vi(sz(ar) - (1 << i) + 1));
                  for(int j = 0; j + (1 << i) <= sz(ar); ++j){
                        rmq[i][j] = max(rmq[i-1][j], rmq[i-1][j + (1 << (i-1))]);
                  }
            }
      }

      int query(int l, int r){
            int k = 31 - __builtin_clz(r - l + 1);
            return max(rmq[k][l], rmq[k][r - (1 << k) + 1]);
      }
};

int main(){
      setIO();

      int N;
      cin >> N;
      vi X(N);
      FOR(i, 0, N) cin >> X[i];

      vi L(N), R(N);
      FOR(i, 0, N){
            if(i == 0) L[i] = 2e9;
            else L[i] = 2 * X[i] - X[i-1];

            if(i == N-1) R[i] = -2e9;
            else R[i] = 2 * X[i] - X[i+1];

//            cout << L[i] << ' ' << R[i] << '\n';
      }

      MaxSPT maxL(L);
      MinSPT minR(R);



      int Q;
      cin >> Q;
      while(Q--){
            int S;
            cin >> S;

            int st = -1;
            int pre = lower_bound(all(X), S) - X.begin();
            if(pre == N){
                  st = pre-1;
            } else if(pre == 0){
                  st = 0;
            } else{
                  if(S - X[pre-1] <= X[pre] - S) st = pre-1;
                  else st = pre;
            }

            ll ans = abs(S - X[st]);

            int l = st, r = st, pos = st;
            while(true){
//                  cout << l << ' ' << r << ' ' << pos << '\n';
                  if(l == 0 && r == N-1) break;

                  if(l == 0){
                        ans += X[N-1] - X[pos];
                        break;
                  }

                  if(r == N-1){
                        ans += X[pos] - X[0];
                        break;
                  }

                  if(X[pos] - X[l-1] <= X[r+1] - X[pos]){
                        int lo = 0, hi = l-1, stop = hi;
                        while(lo <= hi){
                              int mid = (lo + hi) >> 1;
                              if(X[r+1] < maxL.query(mid, l-1)) stop = mid, lo = mid + 1;
                              else hi = mid - 1;
                        }

//                        cout << dbg(stop) << dbg(pos) << "to left\n";
                        ans += abs(X[stop] - X[pos]) + abs(X[stop] - X[r+1]);
                        l = stop;
                        pos = ++r;
                  } else{
                        int lo = r+1, hi = N-1, stop = lo;
                        while(lo <= hi){
                              int mid = (lo + hi) >> 1;
                              if(X[l-1] >= minR.query(r+1, mid)) stop = mid, hi = mid - 1;
                              else lo = mid + 1;
                        }

//                        cout << dbg(stop) << dbg(pos) << "to right\n";
                        ans += abs(X[stop] - X[pos]) + abs(X[stop] - X[l-1]);
                        r = stop;
                        pos = --l;
                  }
            }
            cout << ans << '\n';
      }

      return 0;
}

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