Submission #69847

#	Time	Username	Problem	Language	Result	Execution time	Memory
69847		Vahan	Horses (IOI15_horses)	C++17	100 / 100	578 ms	165480 KiB

horses

#include "horses.h"
#include<cmath>
#include<iostream>
using namespace std;
pair<long double,long long> t[5000008],mec[5000008];
long double lp[600000];
long long p[600000],n,x[600000],y[600000];
long long mod=1000000007;
void build(int l,int r,int v)
{
    t[v].second=1;
    if(l==r)
    {
        t[v].first=lp[l];
        mec[v].first=lp[l];
        t[v].second=p[l];
        mec[v].second=p[l];
        return;
    }
    int mid=(l+r)/2;
    build(l,mid,2*v);
    build(mid+1,r,2*v+1);
    mec[v]=max(mec[2*v],mec[2*v+1]);
}
void update(int L,int R,int l,int r,int v,long long e,long double f)
{
    if(l>r)
        return;
    if(l==L && r==R)
    {
        t[v].first+=f;
        t[v].second*=e;
        mec[v].first+=f;
        mec[v].second*=e;
        mec[v].second%=mod;
        t[v].second%=mod;
        return;
    }
    int mid=(L+R)/2;
    update(L,mid,l,min(mid,r),2*v,e,f);
    update(mid+1,R,max(l,mid+1),r,2*v+1,e,f);
    mec[v]=max(mec[2*v],mec[2*v+1]);
    mec[v].first+=t[v].first;
    mec[v].second*=t[v].second;
    mec[v].second%=mod;
}
int init(int N, int X[], int Y[]) {
    n=N;
    for(int i=0;i<n;i++)
    {
        x[i]=X[i];
        y[i]=Y[i];
    }
    for(int i=0;i<N;i++)
    {
        p[i]=X[i];
        lp[i]+=log(X[i]);
        if(i>0)
        {
            p[i]=(p[i]*p[i-1])%mod;
            lp[i]+=lp[i-1];
        }
    }
    for(int i=0;i<N;i++)
    {
        p[i]=(p[i]*Y[i])%mod;
        lp[i]+=log(Y[i]);
    }
    build(0,n-1,1);
	return mec[1].second;
}
long long binpow(long long a,long long b)
{
    if(b==0)
        return 1;
    if(b%2==0)
    {
        long long arm=binpow(a,b/2);
        return (arm*arm)%mod;
    }
    return (a*binpow(a,b-1))%mod;
}
int updateX(int pos, int val) {
    long long e=(binpow(x[pos],mod-2)*val)%mod;
    long double f=log(val)-log(x[pos]);
    x[pos]=val;
    update(0,n-1,pos,n-1,1,e,f);
	return mec[1].second;
}

int updateY(int pos, int val) {
    long long e=(binpow(y[pos],mod-2)*val)%mod;
    long double f=log(val)-log(y[pos]);
    y[pos]=val;
    update(0,n-1,pos,pos,1,e,f);
	return mec[1].second;
}

Compilation message (stderr)

horses.cpp: In function 'int init(int, int*, int*)':
horses.cpp:69:14: warning: conversion to 'int' from 'long long int' may alter its value [-Wconversion]
     build(0,n-1,1);
             ~^~
horses.cpp:70:16: warning: conversion to 'int' from 'long long int' may alter its value [-Wconversion]
  return mec[1].second;
         ~~~~~~~^~~~~~
horses.cpp: In function 'int updateX(int, int)':
horses.cpp:87:15: warning: conversion to 'int' from 'long long int' may alter its value [-Wconversion]
     update(0,n-1,pos,n-1,1,e,f);
              ~^~
horses.cpp:87:23: warning: conversion to 'int' from 'long long int' may alter its value [-Wconversion]
     update(0,n-1,pos,n-1,1,e,f);
                      ~^~
horses.cpp:88:16: warning: conversion to 'int' from 'long long int' may alter its value [-Wconversion]
  return mec[1].second;
         ~~~~~~~^~~~~~
horses.cpp: In function 'int updateY(int, int)':
horses.cpp:95:15: warning: conversion to 'int' from 'long long int' may alter its value [-Wconversion]
     update(0,n-1,pos,pos,1,e,f);
              ~^~
horses.cpp:96:16: warning: conversion to 'int' from 'long long int' may alter its value [-Wconversion]
  return mec[1].second;
         ~~~~~~~^~~~~~

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