Submission #398539

#	Time	Username	Problem	Language	Result	Execution time	Memory
398539		cfalas	Horses (IOI15_horses)	C++14	100 / 100	797 ms	100632 KiB

horses

#include "horses.h"
#include<bits/stdc++.h>
using namespace std;
#define mp make_pair
#define INF 10000000
#define MOD 1000000007ll
#define MID ((l+r)/2)
#define HASHMOD 2305843009213693951
#define ll long long
#define ull unsigned long long
#define F first
#define S second
typedef pair<ll, ll> ii;
typedef pair<ii, int> iii;
typedef vector<ll> vi;
typedef vector<ii> vii;
typedef map<int, int> mii;

#define EPS 1e-6
#define FOR(i,n) for(int i=0;i<((int)(n));i++)
#define FORi(i,a,b) for(int i=((int)(a));i<((int)(b));i++)
#define FOA(v, a) for(auto v : a)

ll mpow(ll a, ll b){
	if(b==0) return 1;
	if(b==1) return a;
	ll z = mpow(a, b/2);
	z*=z;
	z%=MOD;
	if(b%2) z*=a;
	return z%MOD;
}

ll modinv(ll x){
	return mpow(x, MOD-2);
}
struct seg_tree{
	typedef long double T;
	struct node{
		T val;
		T laz;
		ll val_mod;
		ll laz_mod=1;
		int left=-1;
		int right=-1;
		node() {val=0, laz=0, left=-1, right=-1;}
		node(T v, ll q) {val=v, val_mod=q, laz=0, laz_mod=1, right=-1, left=-1;}
		node(T v) {val=v, val_mod=0, laz=0, laz_mod=1, right=-1, left=-1;}
	};
	vector<node> seg;
	static inline int N;
	const int RAND_VALUE=0;
	seg_tree(int n){N=n, seg.assign(1, node());}

	inline node merge(node par, node a, node b){
		node ret;
		ret.left = par.left, ret.right = par.right;
		ret.val = max(a.val, b.val);
		if(a.val>b.val) ret.val_mod = a.val_mod;
		else ret.val_mod = b.val_mod;
		return ret;
	}

	inline void update_node(ll ind, ll val, ll val_prev, int l, int r){
		//cout<<"change "<<l<<" "<<r<<" by "<<log(val)<<" "<<log(val_prev)<<endl;
		seg[ind].val += (log(val)-log(val_prev));
		seg[ind].val_mod = ((seg[ind].val_mod * modinv(val_prev))%MOD * val)%MOD;
		seg[ind].laz += (log(val)-log(val_prev));
		seg[ind].laz_mod *= (modinv(val_prev) * val)%MOD;
		seg[ind].laz_mod %= MOD;
	}

	inline void down(node &par, int l, int r){
		if(par.laz && par.laz_mod!=1){
			seg[par.left].val += par.laz;
			seg[par.right].val += par.laz;

			seg[par.left].laz += par.laz;
			seg[par.right].laz += par.laz;

			seg[par.left].val_mod = (seg[par.left].val_mod * par.laz_mod)%MOD;
			seg[par.right].val_mod = (seg[par.right].val_mod * par.laz_mod)%MOD;

			seg[par.left].laz_mod *= par.laz_mod;
			seg[par.left].laz_mod %= MOD;
			seg[par.right].laz_mod *= par.laz_mod;
			seg[par.right].laz_mod %= MOD;
		}

		par.laz = 0;
		par.laz_mod = 1;
	}

	inline void create_children(int ind){
		node par = seg[ind];
		if(par.left==-1) par.left=seg.size(), seg.push_back(node());
		if(par.right==-1) par.right=seg.size(), seg.push_back(node());
		seg[ind] = par;
	}

	void build(vector<T>& arr, vector<ll>& arr_mod, int l=0, int r=N-1, int ind=0){
		if(l==r) seg[ind] = node(arr[l], arr_mod[l]);
		else{
			create_children(ind);
			build(arr,arr_mod, l,MID,seg[ind].left);
			build(arr,arr_mod, MID+1,r,seg[ind].right);

			seg[ind] = merge(seg[ind], seg[seg[ind].left], seg[seg[ind].right]);
		}
	}

	void update(int rl, int rr, ll val, ll val_prev, int l=0, int r=N-1, int ind=0){
		if(rl<=l && r<=rr) update_node(ind, val, val_prev,l,r);
		else if(rr<l || r<rl) return;
		else{
			create_children(ind);
			down(seg[ind],l,r);
			update(rl,rr,val, val_prev,l,MID,seg[ind].left);
			update(rl,rr,val, val_prev, MID+1,r,seg[ind].right);
			seg[ind] = merge(seg[ind], seg[seg[ind].left], seg[seg[ind].right]);
		}
	}

	node _query(int rl, int rr, int l=0, int r=N-1, int ind=0){
		if(rl<=l && r<=rr) return seg[ind];
		else if(rl>r || l>rr) return RAND_VALUE;
		else{
			create_children(ind);
			down(seg[ind],l,r);
			return merge(seg[ind], _query(rl, rr, l, MID, seg[ind].left), _query(rl,rr,MID+1,r,seg[ind].right));
		}
	}

	ll query(int l, int r){
		return _query(l,r).val_mod;
	}
	
};


int n;
vi x,y;
seg_tree seg(n);
int init(int N, int X[], int Y[]) {
	n = N;
	seg.N = n;
	x.resize(n);
	y.resize(n);
	FOR(i,n) x[i] = X[i], y[i] = Y[i];
	vector<long double> ly(n);
	vi my(n);
	ly[0] = log(x[0]);
	my[0] = x[0];
	FORi(i,1,n) ly[i] = ly[i-1] + log(x[i]);
	FORi(i,1,n) my[i] = (my[i-1] * x[i])%MOD;
	FOR(i,n) my[i] = (my[i]*y[i])%MOD;
	FOR(i,n) ly[i] += log(y[i]);
	seg.build(ly, my);
	return seg.query(0, n-1);
}

int updateX(int pos, int val) {	
	ll pval = x[pos];
	x[pos] = val;
	seg.update(pos, n-1, val, pval);
	return seg.query(0, n-1);
}

int updateY(int pos, int val) {
	ll pval = y[pos];
	y[pos] = val;
	seg.update(pos, pos, val, pval);
	return seg.query(0, n-1);
}

Compilation message (stderr)

horses.cpp:51:9: warning: inline variables are only available with '-std=c++17' or '-std=gnu++17'
   51 |  static inline int N;
      |         ^~~~~~
horses.cpp: In member function 'void seg_tree::update_node(long long int, long long int, long long int, int, int)':
horses.cpp:64:59: warning: unused parameter 'l' [-Wunused-parameter]
   64 |  inline void update_node(ll ind, ll val, ll val_prev, int l, int r){
      |                                                       ~~~~^
horses.cpp:64:66: warning: unused parameter 'r' [-Wunused-parameter]
   64 |  inline void update_node(ll ind, ll val, ll val_prev, int l, int r){
      |                                                              ~~~~^
horses.cpp: In member function 'void seg_tree::down(seg_tree::node&, int, int)':
horses.cpp:73:34: warning: unused parameter 'l' [-Wunused-parameter]
   73 |  inline void down(node &par, int l, int r){
      |                              ~~~~^
horses.cpp:73:41: warning: unused parameter 'r' [-Wunused-parameter]
   73 |  inline void down(node &par, int l, int r){
      |                                     ~~~~^
horses.cpp: In member function 'void seg_tree::create_children(int)':
horses.cpp:96:37: warning: conversion from 'std::vector<seg_tree::node>::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
   96 |   if(par.left==-1) par.left=seg.size(), seg.push_back(node());
      |                             ~~~~~~~~^~
horses.cpp:97:39: warning: conversion from 'std::vector<seg_tree::node>::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
   97 |   if(par.right==-1) par.right=seg.size(), seg.push_back(node());
      |                               ~~~~~~~~^~
horses.cpp: In function 'int init(int, int*, int*)':
horses.cpp:159:18: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
  159 |  return seg.query(0, n-1);
      |         ~~~~~~~~~^~~~~~~~
horses.cpp: In function 'int updateX(int, int)':
horses.cpp:166:18: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
  166 |  return seg.query(0, n-1);
      |         ~~~~~~~~~^~~~~~~~
horses.cpp: In function 'int updateY(int, int)':
horses.cpp:173:18: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
  173 |  return seg.query(0, n-1);
      |         ~~~~~~~~~^~~~~~~~

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