Submission #422622

#	Time	Username	Problem	Language	Result	Execution time	Memory
422622		vanic	Horses (IOI15_horses)	C++14	100 / 100	756 ms	87336 KiB

horses

#include "horses.h"
#include <algorithm>
#include <cmath>
#include <iostream>

using namespace std;

typedef long long ll;

#define double long double

const int mod=1e9+7, Log=30, maxn=5e5, Log1=19, pot=(1<<Log1);

inline int sum(int a, int b){
	if(a+b>=mod){
		return a+b-mod;
	}
	if(a+b<0){
		return a+b+mod;
	}
	return a+b;
}

inline int mul(int a, int b){
	return (ll)a*b%mod;
}

inline int pote(int a, int b){
	int sol=1;
	for(int i=0; i<Log; i++){
		if((1<<i)&b){
			sol=mul(sol, a);
		}
		a=mul(a, a);
	}
	return sol;
}

inline int dij(int a, int b){
	return mul(a, pote(b, mod-2));
}

pair < double, int > t[pot*2];
pair < double, int > prop[pot*2];
int a[maxn];
int b[maxn];

void precompute(){
	for(int i=1; i<pot*2; i++){
		prop[i]={0, 1};
		t[i]={0, 1};
	}
}

void propagate(int x){
	if(prop[x].second==1){
		return;
	}
	t[x].second=mul(t[x].second, prop[x].second);
	t[x].first=t[x].first+prop[x].first;
	if(x<pot){
		prop[x*2]={prop[x*2].first+prop[x].first, mul(prop[x*2].second, prop[x].second)};
		prop[x*2+1]={prop[x*2+1].first+prop[x].first, mul(prop[x*2+1].second, prop[x].second)};
	}
	prop[x]={0, 1};
}

void update(int L, int D, int x, int l, int d, double val1, int val2){
	propagate(x);
	if(L>=l && D<=d){
		t[x]={t[x].first+val1, mul(t[x].second, val2)};
//		cout << "upd " << x-pot << ' ' << t[x] << endl;
		if(x<pot){
			prop[x*2]={prop[x*2].first+val1, mul(prop[x*2].second, val2)};
			prop[x*2+1]={prop[x*2+1].first+val1, mul(prop[x*2+1].second, val2)};
		}
		return;
	}
	if((L+D)/2>=l){
		update(L, (L+D)/2, x*2, l, d, val1, val2);
	}
	if((L+D)/2+1<=d){
		update((L+D)/2+1, D, x*2+1, l, d, val1, val2);
	}
	propagate(x*2);
	propagate(x*2+1);
	if(t[x*2].first>t[x*2+1].first){
		t[x]=t[x*2];
	}
	else{
		t[x]=t[x*2+1];
	}
}

int init(int n, int x[], int y[]){
	precompute();
	int val=1;
	double val1=0;
	for(int i=0; i<pot; i++){
		if(i<n){
			a[i]=x[i];
			b[i]=y[i];
			val=mul(val, a[i]);
			val1+=log(a[i]);
			update(0, pot-1, 1, i, i, val1+log(b[i]),  mul(val, b[i]));
		}
		else{
			update(0, pot-1, 1, i, i, val1, val);
		}
	}
	return t[1].second;
}

int updateX(int pos, int val){
	update(0, pot-1, 1, pos, pot-1, log(val)-log(a[pos]), dij(val, a[pos]));
	a[pos]=val;
	return t[1].second;
}

int updateY(int pos, int val){
//	cout << "val " << b[pos] << ' ' << val << endl;
	update(0, pot-1, 1, pos, pos, log(val)-log(b[pos]), dij(val, b[pos]));
	b[pos]=val;
	return t[1].second;
}
/*

int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	int n;
	cin >> n;
	int x[n], y[n];
	for(int i=0; i<n; i++){
		cin >> x[i];
	}
	for(int i=0; i<n; i++){
		cin >> y[i];
	}
	cout << init(n, x, y) << '\n';
	int q;
	cin >> q;
	int a1, b1, c1;
	for(int i=0; i<q; i++){
		cin >> a1 >> b1 >> c1;
		if(a1==1){
			cout << updateX(b1, c1) << '\n';
		}
		else{
			cout << updateY(b1, c1) << '\n';
		}
	}
	return 0;
}
*/

Compilation message (stderr)

horses.cpp: In function 'int mul(int, int)':
horses.cpp:25:16: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
   25 |  return (ll)a*b%mod;
      |         ~~~~~~~^~~~

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