Submission #767985

#	Time	Username	Problem	Language	Result	Execution time	Memory
767985		marvinthang	Bitaro's travel (JOI23_travel)	C++17	100 / 100	473 ms	70688 KiB

travel

/*************************************
*    author: marvinthang             *
*    created: 22.03.2023 15:18:27    *
*************************************/

#include <bits/stdc++.h>

using namespace std;

#define                  fi  first
#define                  se  second
#define                left  ___left
#define               right  ___right
#define                TIME  (1.0 * clock() / CLOCKS_PER_SEC)
#define             MASK(i)  (1LL << (i))
#define           BIT(x, i)  ((x) >> (i) & 1)
#define  __builtin_popcount  __builtin_popcountll
#define              ALL(v)  (v).begin(), (v).end()
#define           REP(i, n)  for (int i = 0, _n = (n); i < _n; ++i)
#define          REPD(i, n)  for (int i = (n); i--; )
#define        FOR(i, a, b)  for (int i = (a), _b = (b); i < _b; ++i) 
#define       FORD(i, b, a)  for (int i = (b), _a = (a); --i >= _a; ) 
#define       FORE(i, a, b)  for (int i = (a), _b = (b); i <= _b; ++i) 
#define      FORDE(i, b, a)  for (int i = (b), _a = (a); i >= _a; --i) 
#define        scan_op(...)  istream & operator >> (istream &in, __VA_ARGS__ &u)
#define       print_op(...)  ostream & operator << (ostream &out, const __VA_ARGS__ &u)
#ifdef LOCAL
    #include "debug.h"
#else
    #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
    #define DB(...) 23
    #define db(...) 23
    #define debug(...) 23
#endif

template <class U, class V> scan_op(pair <U, V>)  { return in >> u.fi >> u.se; }
template <class T> scan_op(vector <T>)  { for (size_t i = 0; i < u.size(); ++i) in >> u[i]; return in; }
template <class U, class V> print_op(pair <U, V>)  { return out << '(' << u.first << ", " << u.second << ')'; }
template <size_t i, class T> ostream & print_tuple_utils(ostream &out, const T &tup) { if constexpr(i == tuple_size<T>::value) return out << ")";  else return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup); }
template <class ...U> print_op(tuple<U...>) { return print_tuple_utils<0, tuple<U...>>(out, u); }
template <class Con, class = decltype(begin(declval<Con>()))> typename enable_if <!is_same<Con, string>::value, ostream&>::type operator << (ostream &out, const Con &con) { out << '{'; for (__typeof(con.begin()) it = con.begin(); it != con.end(); ++it) out << (it == con.begin() ? "" : ", ") << *it; return out << '}'; }

// end of template

const long long INF = 1e18;
const int MAX = 2e5 + 5;
const int LOG = 20;

int N, Q;
long long X[MAX];
long long rmq[2][MAX][LOG];

void init(void) {
	cin >> N;
	X[0] = -INF;
	X[N + 1] = INF;
	FORE(i, 1, N) cin >> X[i];	
	FORE(i, 1, N) {
		rmq[0][i][0] = 2 * X[i + 1] - X[i];
		rmq[1][i][0] = 2 * X[i - 1] - X[i];	
	}
	FOR(k, 1, LOG) FORE(i, 1, N - MASK(k) + 1) {
		rmq[0][i][k] = max(rmq[0][i][k - 1], rmq[0][i + MASK(k - 1)][k - 1]);
		rmq[1][i][k] = min(rmq[1][i][k - 1], rmq[1][i + MASK(k - 1)][k - 1]);
	}
	cin >> Q;
}

long long get_max0(int i, int j) {
	if (j < i) return -INF;
	int h = __lg(j - i + 1);
	return max(rmq[0][i][h], rmq[0][j - MASK(h) + 1][h]);
}

long long get_min1(int i, int j) {
	if (j < i) return INF;
	int h = __lg(j - i + 1);
	return min(rmq[1][i][h], rmq[1][j - MASK(h) + 1][h]);
}

long long go(long long s) {
	int p = lower_bound(X + 1, X + 1 + N, s) - X;
	int l, r;
	long long res = 0;	
	bool left = true;
	if (s - X[p - 1] <= X[p] - s) {
		l = r = p - 1;
		res = s - X[p - 1];
	} else {
		l = r = p;
		res = X[p] - s;
	}
	while (l > 1 || r < N) {
		if (left) {
			int low = 1, high = l;
			while (low <= high) {
				int m = low + high >> 1;
				if (get_max0(m, l - 1) <= X[r + 1]) high = m - 1;
				else low = m + 1;
			}
			res += X[l] - X[low];
			l = low;
			if (r < N) res += X[++r] - X[l];
			left = false;
		} else {
			int low = r, high = N;
			while (low <= high) {
				int m = low + high >> 1;
				if (get_min1(r + 1, m) > X[l - 1]) low = m + 1;
				else high = m - 1;
			}
			res += X[high] - X[r];
			r = high;
			if (l > 1) res += X[r] - X[--l];
			left = true;
		}
	}
	return res;
}

void process(void) {
	while (Q--) {
		int s; cin >> s;
		cout << go(s) << '\n';
	}
}

int main(void) {
	ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
	file("travel");
	init();
	process();
	cerr << "Time elapsed: " << TIME << " s.\n";
	return (0^0);
}

Compilation message (stderr)

travel.cpp: In function 'long long int go(long long int)':
travel.cpp:97:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   97 |     int m = low + high >> 1;
      |             ~~~~^~~~~~
travel.cpp:108:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  108 |     int m = low + high >> 1;
      |             ~~~~^~~~~~
travel.cpp: In function 'int main()':
travel.cpp:30:61: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
travel.cpp:130:2: note: in expansion of macro 'file'
  130 |  file("travel");
      |  ^~~~
travel.cpp:30:94: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                                                       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
travel.cpp:130:2: note: in expansion of macro 'file'
  130 |  file("travel");
      |  ^~~~

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