Submission #1029181

#	Time	Username	Problem	Language	Result	Execution time	Memory
1029181		marvinthang	Flooding Wall (BOI24_wall)	C++17	100 / 100	1731 ms	125540 KiB

Main

/*************************************
*    author: marvinthang             *
*    created: 06.05.2024 16:21:48    *
*************************************/

#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-- > 0; )
#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.first >> u.second; }
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 << '}'; }

const int MOD = 1e9 + 7;
namespace MODULAR {
    inline void fasterLLDivMod(unsigned long long x, unsigned y, unsigned &out_d, unsigned &out_m) {
        unsigned xh = (unsigned)(x >> 32), xl = (unsigned)x, d, m;
    #ifdef __GNUC__
        asm(
            "divl %4 \n\t"
            : "=a" (d), "=d" (m)
            : "d" (xh), "a" (xl), "r" (y)
        );
    #else
        __asm {
            mov edx, dword ptr[xh];
            mov eax, dword ptr[xl];
            div dword ptr[y];
            mov dword ptr[d], eax;
            mov dword ptr[m], edx;
        };
    #endif
        out_d = d; out_m = m;
    }
    template <class T> T invGeneral(T a, T b) {
        a %= b;
        if (!a) return b == 1 ? 0 : -1;
        T x = invGeneral(b, a);
        return x == -1 ? -1 : ((1 - 1LL * b * x) / a + b) % b;
    }
    template <int MOD> struct ModInt {
        unsigned int val;
        ModInt(void): val(0) {}
        ModInt(const long long &x) { *this = x; }
        ModInt & normalize(const unsigned int &v) {
            val = v >= MOD ? v - MOD : v;
            return *this;
        }
        bool operator ! (void) { return !val; }
        ModInt & operator = (const ModInt &x) { val = x.val; return *this; }
        ModInt & operator = (const long long &x) { return normalize(x % MOD + MOD); }
        ModInt operator - (void) { return ModInt(MOD - val); }
        ModInt & operator += (const ModInt &other) { return normalize(val + other.val); }
        ModInt & operator -= (const ModInt &other) { return normalize(val + MOD - other.val); }
        ModInt & operator /= (const ModInt &other) { return *this *= other.inv(); }
        ModInt & operator *= (const ModInt &other) {
            unsigned dummy;
            fasterLLDivMod((unsigned long long) val * other.val, MOD, dummy, val);
            return *this;
        }
        ModInt operator + (const ModInt &other) const { return ModInt(*this) += other; }
        ModInt operator - (const ModInt &other) const { return ModInt(*this) -= other; }
        ModInt operator * (const ModInt &other) const { return ModInt(*this) *= other; }
        ModInt operator / (const ModInt &other) const { return ModInt(*this) /= other; }
        ModInt pow(long long n) const {
            assert(n >= 0);
            ModInt res = 1, a = *this;
            for (; n; n >>= 1, a *= a) if (n & 1) res *= a;
            return res;
        }
        ModInt inv(void) const {
            int i = invGeneral((int) val, MOD);
            assert(~i);
            return i;
        }
        ModInt & operator ++ (void) { return *this += 1; }
        ModInt & operator -- (void) { return *this -= 1; }
        ModInt operator ++ (int) { ModInt old = *this; operator ++(); return old; }
        ModInt operator -- (int) { ModInt old = *this; operator --(); return old; }
        friend ModInt operator + (const long long &x, const ModInt &y) { return ModInt(x) + y; }
        friend ModInt operator - (const long long &x, const ModInt &y) { return ModInt(x) - y; }
        friend ModInt operator * (const long long &x, const ModInt &y) { return ModInt(x) * y; }
        friend ModInt operator / (const long long &x, const ModInt &y) { return ModInt(x) / y; }
        friend ostream & operator << (ostream &out, const ModInt &x) { return out << x.val; }
        friend istream & operator >> (istream &in, ModInt &x) { long long a; in >> a; x = a; return in; }
        explicit operator bool(void) const { return val; }
        explicit operator int(void) const { return val; }
    };  
    using Modular = ModInt <MOD>;
}
using namespace MODULAR;

// end of template

vector <Modular> pw2, pw_inv2;

struct SegmentTree {
	int n;
	vector <Modular> st;
	vector <int> lazy;
	SegmentTree(const vector <Modular> &val) {
		n = val.size();	
		st.resize(n * 4 + 23);
		lazy.resize(n * 4 + 23);
		build(1, 0, n, val);
	}
	void build(int i, int l, int r, const vector <Modular> &val) {
		if (r - l == 1) {
			st[i] = val[l];
			return;
		}
		int m = l + r >> 1;
		build(i << 1, l, m, val);
		build(i << 1 | 1, m, r, val);
		st[i] = st[i << 1] + st[i << 1 | 1];
	}
	void apply(int i, int v) {
	}
	void pushDown(int i) {
		if (lazy[i]) {
			Modular v = lazy[i] > 0 ? pw2[lazy[i]] : pw_inv2[-lazy[i]];
			st[i << 1] *= v;
			st[i << 1 | 1] *= v;
			lazy[i << 1] += lazy[i];
			lazy[i << 1 | 1] += lazy[i];
			lazy[i] = 0;
		}
	}
	void update(int i, int l, int r, int u, int v, int val) {
		if (l >= v || r <= u || u >= v) return;
		if (u <= l && r <= v) {
			lazy[i] += val;
			st[i] *= (val > 0 ? pw2[val] : pw_inv2[-val]);
			return;
		}
		pushDown(i);
		int m = l + r >> 1;
		update(i << 1, l, m, u, v, val);
		update(i << 1 | 1, m, r, u, v, val);
		st[i] = st[i << 1] + st[i << 1 | 1];
	}
	Modular get(int i, int l, int r, int u, int v) {
		if (l >= v || r <= u || u >= v) return 0;
		if (u <= l && r <= v) return st[i];
		pushDown(i);
		int m = l + r >> 1;
		return get(i << 1, l, m, u, v) + get(i << 1 | 1, m, r, u, v);
	}
	void update(int l, int r, int v) {
		update(1, 0, n, l, r, v);
	}
	Modular get(int l, int r) {
		return get(1, 0, n, l, r);
	}
};

void process(void) {
	int n; cin >> n;
	vector <int> a(n), b(n); cin >> a >> b;
	vector <int> c(a); c.insert(c.end(), ALL(b));
	sort(ALL(c)); c.erase(unique(ALL(c)), c.end());
	int m = c.size();
	REP(i, n) {
		a[i] = lower_bound(ALL(c), a[i]) - c.begin();
		b[i] = lower_bound(ALL(c), b[i]) - c.begin();
		if (a[i] > b[i]) swap(a[i], b[i]);
	}
	Modular res;
	pw2.resize(n + 1);
	pw_inv2.resize(n + 1);
	pw2[0] = pw_inv2[0] = 1;
	Modular inv2 = Modular(2).inv();
	FORE(i, 1, n) pw2[i] = pw2[i - 1] + pw2[i - 1];
	FORE(i, 1, n) pw_inv2[i] = pw_inv2[i - 1] * inv2;

	vector <Modular> v(m);
	REP(i, m) v[i] = c[i] - (i ? c[i - 1] : 0);
	SegmentTree st_pref(v);

	vector <int> cnt(m);
	REP(i, n) ++cnt[b[i]];
	int cur = 0;
	REP(i, m) {
		v[i] *= pw2[cur];
		cur += cnt[i];
	}
	SegmentTree st_suff(v), st_pxs(v);

	vector <int> suff(n);
	REPD(i, n - 1) suff[i] = max(suff[i + 1], a[i + 1]);
	int pref = 0;
	REP(i, n) {
		st_suff.update(b[i] + 1, m, -1);
		st_pxs.update(b[i] + 1, m, -1);
		auto calc = [&] (int v) {
			Modular cur = pw2[n - 1] * (c.back() - c[v]), a, b, ab;
			cur -= st_pref.get(max(v, pref) + 1, m) * pw2[n - i - 1];
			cur -= st_suff.get(max(v, suff[i]) + 1, m) * pw2[i];
			cur += st_pxs.get(max({v, pref, suff[i]}) + 1, m);
			return cur;
		};
		res += calc(a[i]) + calc(b[i]);
		st_pref.update(b[i] + 1, m, +1);
		st_pxs.update(b[i] + 1, m, +1);
		pref = max(pref, a[i]);
	}
	cout << res << '\n';
}

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

Compilation message (stderr)

Main.cpp: In member function 'void SegmentTree::build(int, int, int, const std::vector<MODULAR::ModInt<1000000007> >&)':
Main.cpp:141:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  141 |   int m = l + r >> 1;
      |           ~~^~~
Main.cpp: In member function 'void SegmentTree::update(int, int, int, int, int, int)':
Main.cpp:166:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  166 |   int m = l + r >> 1;
      |           ~~^~~
Main.cpp: In member function 'MODULAR::Modular SegmentTree::get(int, int, int, int, int)':
Main.cpp:175:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  175 |   int m = l + r >> 1;
      |           ~~^~~
Main.cpp: In function 'int main()':
Main.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); }
      |                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:241:2: note: in expansion of macro 'file'
  241 |  file("wall");
      |  ^~~~
Main.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); }
      |                                                                                       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:241:2: note: in expansion of macro 'file'
  241 |  file("wall");
      |  ^~~~

• Subtask 1: 8 / 8
• Subtask 2: 17 / 17
• Subtask 3: 19 / 19
• Subtask 4: 14 / 14
• Subtask 5: 12 / 12
• Subtask 6: 30 / 30