Submission #204775

#	Time	Username	Problem	Language	Result	Execution time	Memory
204775		TAISA_	Horses (IOI15_horses)	C++14	37 / 100	346 ms	49272 KiB

horses

#include "horses.h"
#include <bits/stdc++.h>
using namespace std;
using ll=long long;
using P=pair<int,int>;
int x[500000],y[500000];
int n;
const ll mod=1000000007LL;
struct segtree{
	int n;
	vector<ll> dat;
	void build(int n_){
		n=1;
		while(n<n_)n<<=1;
		dat.resize(2*n,1);
	}
	void upd(int k,ll s){
		k+=n;
		dat[k]=s%mod;
		k>>=1;
		while(k>0){
			dat[k]=dat[k<<1]*dat[k<<1|1]%mod;
			k>>=1;
		}
	}
	ll get(int a,int b,int k,int l,int r){
		if(b<=l||r<=a)return 1LL;
		if(a<=l&&r<=b)return dat[k]%mod;
		int m=(l+r)/2;
		return get(a,b,k<<1,l,m)*get(a,b,k<<1|1,m,r)%mod;
	}
	ll get(int a,int b){return get(a,b,1,0,n);}
} seg;
struct RMQ{
	int n;
	vector<ll> dat;
	void build(int n_){
		n=1;
		while(n<n_)n<<=1;
		dat.resize(2*n,0);
	}
	void upd(int k,ll s){
		k+=n;
		dat[k]=s;
		k>>=1;
		while(k>0){
			dat[k]=max(dat[k<<1],dat[k<<1|1]);
			k>>=1;
		}
	}
	ll get(int a,int b,int k,int l,int r){
		if(b<=l||r<=a)return 0;
		if(a<=l&&r<=b)return dat[k];
		int m=(l+r)/2;
		return max(get(a,b,k<<1,l,m),get(a,b,k<<1|1,m,r));
	}
	ll get(int a,int b){return get(a,b,1,0,n);}
} rmq;
set<P> st;
ll calc(){
	ll id=n-1,t=x[n-1];
	for(int i=n-2;i>=0;i--){
		if(y[i]>t*y[id]){
			id=i;
			t=1;
		}
		t*=x[i];
		if(t>=mod){
			break;
		}
	} 
	return y[id]*seg.get(0,id+1)%mod;
}
int init(int N, int X[], int Y[]) {
	n=N;
	seg.build(n+10);
	rmq.build(n+10);
	int l=0;
	for(int i=0;i<n;i++){
		x[i]=X[i];
		y[i]=Y[i];
		if(x[i]!=1){
			if(i>0)st.insert(P(l,i-1));
			l=i;
		}
		seg.upd(i,x[i]);
		rmq.upd(i,y[i]);
	}
	st.insert(P(l,n-1));
	return calc();
}
int updateX(int pos, int val) {	
	if(x[pos]==val)return calc();
	if(x[pos]==1){
		auto it=prev(st.lower_bound(P(pos+1,0)));
		st.insert(P(pos,it->second));
		if(it->first!=pos)st.insert(P(it->first,pos-1));
		st.erase(it);
	}else if(val==1){
		auto it=prev(st.lower_bound(P(pos+1,0)));
		if(it!=st.begin()){
			auto i2=prev(it);
			st.insert(P(i2->first,it->second));
			st.erase(i2);
			st.erase(it);
		}
	}
	x[pos]=val;
	seg.upd(pos,val);
	return calc();
}

int updateY(int pos, int val) {
	y[pos]=val;
	rmq.upd(pos,val);
	return calc();
}

Compilation message (stderr)

horses.cpp: In function 'll calc()':
horses.cpp:72:27: warning: conversion to 'int' from 'll {aka long long int}' may alter its value [-Wconversion]
  return y[id]*seg.get(0,id+1)%mod;
                         ~~^~
horses.cpp: In function 'int init(int, int*, int*)':
horses.cpp:90:13: warning: conversion to 'int' from 'll {aka long long int}' may alter its value [-Wconversion]
  return calc();
         ~~~~^~
horses.cpp: In function 'int updateX(int, int)':
horses.cpp:93:28: warning: conversion to 'int' from 'll {aka long long int}' may alter its value [-Wconversion]
  if(x[pos]==val)return calc();
                        ~~~~^~
horses.cpp:110:13: warning: conversion to 'int' from 'll {aka long long int}' may alter its value [-Wconversion]
  return calc();
         ~~~~^~
horses.cpp: In function 'int updateY(int, int)':
horses.cpp:116:13: warning: conversion to 'int' from 'll {aka long long int}' may alter its value [-Wconversion]
  return calc();
         ~~~~^~

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