Submission #707004

#	Time	Username	Problem	Language	Result	Execution time	Memory
707004		marvinthang	Horses (IOI15_horses)	C++17	0 / 100	584 ms	42624 KiB

horses

/*************************************
*    author: marvinthang             *
*    created: 08.03.2023 15:25:43    *
*************************************/

#include "horses.h"
#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)

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> scan_op(pair <U, V>)  { return in >> u.fi >> u.se; }
template <class U, class V> print_op(pair <U, V>)  { return out << '(' << u.first << ", " << u.second << ')'; }
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 << '}'; }
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 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;
}

// end of template

const int MOD = 1e9 + 7;
const int MAX = 5e5 + 5;

int N, X[MAX], Y[MAX], bit[MAX], st[MAX << 2];
set <int, greater <int>> pos;

void build(int i, int l, int r) {
	if (r - l == 1) {
		st[i] = Y[l];
		return;
	}
	int m = l + r >> 1;
	build(i << 1, l, m);
	build(i << 1 | 1, m, r);
	st[i] = max(st[i << 1], st[i << 1 | 1]);
}

void update(int i, int l, int r, int p) {
	if (r - l == 1) {
		st[i] = Y[l];
		return;
	}
	int m = l + r >> 1;
	if (p < m) update(i << 1, l, m, p);
	else update(i << 1 | 1, m, r, p);
	st[i] = max(st[i << 1], st[i << 1 | 1]);
}

int getMax(int i, int l, int r, int u, int v) {
	if (l >= v || r <= u) return 0;
	if (u <= l && r <= v) return st[i];
	int m = l + r >> 1;
	return max(getMax(i << 1, l, m, u, v), getMax(i << 1 | 1, m, r, u, v));
}

void update(int i, int v) {
	for (++i; i <= N; i += i & -i) bit[i] = 1LL * bit[i] * v % MOD;
}

int getMul(int i) {
	int res = 1;
	for (++i; i > 0; i &= i - 1) res = 1LL * res * bit[i] % MOD;
	return res;
}

int solve(void) {
	int res = -1;
	long long cb = 1;
	int r = N, ma = 0, mb = 0;
	cout << getMul(2) << '\n';
	for (int l: pos) {
		int ca = getMax(1, 0, N, l, r);
		// ma / ca * cb / mb > 1
		// ma * cb > ca * mb
		if (1LL * ca * mb >= 1LL * ma * cb) {
			res = 1LL * getMul(l) * ca % MOD;
			ma = ca; mb = cb;
		}
		// cout << l << ' ' << r << ' ' << ca << ' ' << cb << ' ' << res << '\n';
		cb *= X[l];
		if (cb > MOD) break;
		r = l;
	}
	// cout << "-------\n";
	return res;
}

int init(int n, int x[], int y[]) {
	N = n;
	fill(bit, bit + N + 1, 1);
	REP(i, N) {
		X[i] = x[i]; Y[i] = y[i];
		if (!i || X[i] != 1) {
			update(i, X[i]);
			pos.insert(i);
		}
	}
	build(1, 0, N);
	return solve();
}

int updateX(int i, int val) {	
	if (X[i] != 1) {
		update(i, invGeneral(X[i], MOD));
		pos.erase(i);
	}
	X[i] = val;
	if (!i || X[i] != 1) {
		update(i, X[i]);
		pos.insert(i);
	}
	return solve();
}

int updateY(int i, int val) {
	Y[i] = val;
	update(1, 0, N, i);
	return solve();
}

#ifdef LOCAL
static char _buffer[1024];
static int _currentChar = 0;
static int _charsNumber = 0;
static FILE *_inputFile, *_outputFile;

static inline int _read() {
    if (_charsNumber < 0) {
        exit(1);
    }
    if (!_charsNumber || _currentChar == _charsNumber) {
        _charsNumber = (int)fread(_buffer, sizeof(_buffer[0]), sizeof(_buffer), _inputFile);
        _currentChar = 0;
    }
    if (_charsNumber <= 0) {
        return -1;
    }
    return _buffer[_currentChar++];
}

static inline int _readInt() {
    int c, x, s;
    c = _read();
    while (c <= 32) c = _read();
    x = 0;
    s = 1;
    if (c == '-') {
        s = -1;
        c = _read();
    }
    while (c > 32) {
        x *= 10;
        x += c - '0';
        c = _read();
    }
    if (s < 0) x = -x;
    return x;
}


int main() {
	_inputFile = fopen("horses.in", "rb");
	_outputFile = fopen("horses.out", "w");
	
	int N; N = _readInt();

	int *X = (int*)malloc(sizeof(int)*(unsigned int)N);
	int *Y = (int*)malloc(sizeof(int)*(unsigned int)N);

	for (int i = 0; i < N; i++) {
		X[i] = _readInt();
	}

	for (int i = 0; i < N; i++) {
		Y[i] = _readInt();
	}	

	fprintf(_outputFile,"%d\n",init(N,X,Y));

	int M; M = _readInt();

	for (int i = 0; i < M; i++) {
		int type; type = _readInt();
		int pos; pos = _readInt();
		int val; val = _readInt(); 

		if (type == 1) {
			fprintf(_outputFile,"%d\n",updateX(pos,val));
		} else if (type == 2) {
			fprintf(_outputFile,"%d\n",updateY(pos,val));
		}
	}

	return 0;
}
#endif

Compilation message (stderr)

horses.cpp: In function 'void build(int, int, int)':
horses.cpp:55:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   55 |  int m = l + r >> 1;
      |          ~~^~~
horses.cpp: In function 'void update(int, int, int, int)':
horses.cpp:66:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   66 |  int m = l + r >> 1;
      |          ~~^~~
horses.cpp: In function 'int getMax(int, int, int, int, int)':
horses.cpp:75:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   75 |  int m = l + r >> 1;
      |          ~~^~~
horses.cpp: In function 'void update(int, int)':
horses.cpp:80:59: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   80 |  for (++i; i <= N; i += i & -i) bit[i] = 1LL * bit[i] * v % MOD;
      |                                          ~~~~~~~~~~~~~~~~~^~~~~
horses.cpp: In function 'int getMul(int)':
horses.cpp:85:56: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   85 |  for (++i; i > 0; i &= i - 1) res = 1LL * res * bit[i] % MOD;
      |                                     ~~~~~~~~~~~~~~~~~~~^~~~~
horses.cpp: In function 'int solve()':
horses.cpp:99:31: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   99 |    res = 1LL * getMul(l) * ca % MOD;
      |          ~~~~~~~~~~~~~~~~~~~~~^~~~~
horses.cpp:100:18: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
  100 |    ma = ca; mb = cb;
      |                  ^~
horses.cpp: In instantiation of 'T invGeneral(T, T) [with T = int]':
horses.cpp:127:33:   required from here
horses.cpp:39:20: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   39 |     return x == -1 ? -1 : ((1 - 1LL * b * x) / a + b) % b;
      |            ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 17
• Subtask 2: 0 / 17
• Subtask 3: 0 / 20
• Subtask 4: 0 / 23
• Subtask 5: 0 / 23