Submission #438516

#	Time	Username	Problem	Language	Result	Execution time	Memory
438516		adamjinwei	Horses (IOI15_horses)	C++14	100 / 100	665 ms	52908 KiB

horses

#include <bits/stdc++.h>
#include "horses.h"
#define lowbit(x) (x&(-x))
#define lson (p<<1)
#define rson (p<<1|1)
#define inf 1000000007
#define mod 1000000007
#define rnd() rand_num()
#define bigrnd() dis(rand_num)
//#pragma GCC optimize("Ofast","inline","-ffast-math")
//#pragma GCC target("avx,sse2,sse3,sse4,mmx")
#define int long long
using namespace std;
unsigned sed=std::chrono::system_clock::now().time_since_epoch().count();
mt19937 rand_num(sed);
uniform_int_distribution<long long> dis(0,inf);
template <typename T> void read(T &x){
	x=0;char ch=getchar();int fh=1;
	while (ch<'0'||ch>'9'){if (ch=='-')fh=-1;ch=getchar();}
	while (ch>='0'&&ch<='9')x=x*10+ch-'0',ch=getchar();
	x*=fh;
}
template <typename T> void write(T x) {
	if (x<0) x=-x,putchar('-');
	if (x>9) write(x/10);
	putchar(x%10+'0');
}
template <typename T> void writeln(T x) {
	write(x);
	puts("");
}
int n;
long long x[500005],y[500005];
long long bit[500005];
double mx[2000005],tag[2000005];
int mxid[2000005];
long long qpow(long long a,long long b)
{
	long long res=1;
	while(b)
	{
		if(b&1) res=res*a%mod;
		a=a*a%mod;
		b>>=1;
	}
	return res;
}
void bitmodify(int x,long long y)
{
	while(x<=n)
	{
		bit[x]*=y;
		bit[x]%=mod;
		x+=lowbit(x);
	}
}
long long bitquery(int x)
{
	long long res=1;
	while(x)
	{
		res*=bit[x];
		res%=mod;
		x-=lowbit(x);
	}
	return res;
}
void pushup(int p)
{
	if(mx[lson]>mx[rson])
	{
		mx[p]=mx[lson];
		mxid[p]=mxid[lson];
	}
	else
	{
		mx[p]=mx[rson];
		mxid[p]=mxid[rson];
	}
}
void build(int p,int l,int r)
{
	if(l==r)
	{
		mx[p]=0;
		mxid[p]=l;
		return;
	}
	int mid=l+r>>1;
	build(lson,l,mid);
	build(rson,mid+1,r);
	pushup(p);
}
void pushdown(int p)
{
	mx[lson]+=tag[p];
	tag[lson]+=tag[p];
	mx[rson]+=tag[p];
	tag[rson]+=tag[p];
	tag[p]=0;
}
void modify(int p,int l,int r,int x,int y,double k)
{
	if(x<=l&&r<=y)
	{
		mx[p]+=k;
		tag[p]+=k;
		return;
	}
	int mid=l+r>>1;
	pushdown(p);
	if(x<=mid) modify(lson,l,mid,x,y,k);
	if(mid+1<=y) modify(rson,mid+1,r,x,y,k);
	pushup(p);
}
signed init(signed N,signed X[],signed Y[])
{
	n=N;
	for(int i=1;i<=n;++i)
	{
		x[i]=X[i-1];
		y[i]=Y[i-1];
		bit[i]=1;
	}
	build(1,1,n);
	for(int i=1;i<=n;++i)
	{
		bitmodify(i,x[i]);
		modify(1,1,n,i,n,log(x[i])/log(2));
		modify(1,1,n,i,i,log(y[i])/log(2));
	}
	return bitquery(mxid[1])*y[mxid[1]]%mod;
}
signed updateX(signed pos,signed val)
{
	pos++;
	modify(1,1,n,pos,n,-log(x[pos])/log(2));
	modify(1,1,n,pos,n,log(val)/log(2));
	bitmodify(pos,qpow(x[pos],mod-2));
	bitmodify(pos,val);
	x[pos]=val;
	return bitquery(mxid[1])*y[mxid[1]]%mod;
}
signed updateY(signed pos,signed val)
{
	pos++;
	modify(1,1,n,pos,pos,-log(y[pos])/log(2));
	modify(1,1,n,pos,pos,log(val)/log(2));
	y[pos]=val;
	return bitquery(mxid[1])*y[mxid[1]]%mod;
}

Compilation message (stderr)

horses.cpp:14:71: warning: conversion from 'std::chrono::duration<long int, std::ratio<1, 1000000000> >::rep' {aka 'long int'} to 'unsigned int' may change value [-Wconversion]
   14 | unsigned sed=std::chrono::system_clock::now().time_since_epoch().count();
      |              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~
horses.cpp: In function 'void bitmodify(long long int, long long int)':
horses.cpp:48:32: warning: declaration of 'y' shadows a global declaration [-Wshadow]
   48 | void bitmodify(int x,long long y)
      |                      ~~~~~~~~~~^
horses.cpp:33:21: note: shadowed declaration is here
   33 | long long x[500005],y[500005];
      |                     ^
horses.cpp:48:20: warning: declaration of 'x' shadows a global declaration [-Wshadow]
   48 | void bitmodify(int x,long long y)
      |                    ^
horses.cpp:33:11: note: shadowed declaration is here
   33 | long long x[500005],y[500005];
      |           ^
horses.cpp: In function 'long long int bitquery(long long int)':
horses.cpp:57:24: warning: declaration of 'x' shadows a global declaration [-Wshadow]
   57 | long long bitquery(int x)
      |                        ^
horses.cpp:33:11: note: shadowed declaration is here
   33 | long long x[500005],y[500005];
      |           ^
horses.cpp: In function 'void build(long long int, long long int, long long int)':
horses.cpp:89:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   89 |  int mid=l+r>>1;
      |          ~^~
horses.cpp: In function 'void modify(long long int, long long int, long long int, long long int, long long int, double)':
horses.cpp:102:41: warning: declaration of 'y' shadows a global declaration [-Wshadow]
  102 | void modify(int p,int l,int r,int x,int y,double k)
      |                                         ^
horses.cpp:33:21: note: shadowed declaration is here
   33 | long long x[500005],y[500005];
      |                     ^
horses.cpp:102:35: warning: declaration of 'x' shadows a global declaration [-Wshadow]
  102 | void modify(int p,int l,int r,int x,int y,double k)
      |                                   ^
horses.cpp:33:11: note: shadowed declaration is here
   33 | long long x[500005],y[500005];
      |           ^
horses.cpp:110:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  110 |  int mid=l+r>>1;
      |          ~^~
horses.cpp: In function 'int init(int, int*, int*)':
horses.cpp:132:37: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
  132 |  return bitquery(mxid[1])*y[mxid[1]]%mod;
      |                                     ^
horses.cpp: In function 'int updateX(int, int)':
horses.cpp:142:37: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
  142 |  return bitquery(mxid[1])*y[mxid[1]]%mod;
      |                                     ^
horses.cpp: In function 'int updateY(int, int)':
horses.cpp:150:37: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
  150 |  return bitquery(mxid[1])*y[mxid[1]]%mod;
      |                                     ^

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