Submission #28071

#	Time	Username	Problem	Language	Result	Execution time	Memory
28071		top34051	Horses (IOI15_horses)	C++14	100 / 100	1153 ms	146576 KiB

horses

#include "horses.h"
#include<bits/stdc++.h>
using namespace std;
#define maxn 1000005
#define pdl pair<double,long long>
#define mod (long long)1000000007

int n;
long long a[maxn];
long long b[maxn];
pdl tree[maxn*4];
pdl lazy[maxn*4];

pdl fus(pdl x,pdl y) {
    return {x.first+y.first,(x.second*y.second+mod)%mod};
}

long long inv(long long value){
    if(value == 1) return 1;
    long long tmp = (inv(mod%value)*((-mod)/value));
    tmp %= mod;
    if(tmp < 0) tmp += mod;
    return tmp;
}

void upd(int now) {
    tree[now] = fus(tree[now],lazy[now]);
    lazy[now<<1] = fus(lazy[now<<1],lazy[now]);
    lazy[now<<1|1] = fus(lazy[now<<1|1],lazy[now]);
    lazy[now] = {0,1};
}

void update(int now,int l,int r,int x,int y,double val1,long long val2) {
    upd(now);
    if(l>r || l>y || r<x) return ;
    if(x<=l && r<=y) {
        lazy[now] = {val1,val2};
        upd(now);
        return ;
    }
    int mid = (l+r)/2;
    update(now<<1,l,mid,x,y,val1,val2); update(now<<1|1,mid+1,r,x,y,val1,val2);
    tree[now] = max(tree[now<<1],tree[now<<1|1]);
}

void build(int now,int l,int r) {
    if(l==r) {
        tree[now] = lazy[now] = {0,1};
        return ;
    }
    int mid = (l+r)/2;
    build(now<<1,l,mid); build(now<<1|1,mid+1,r);
    tree[now] = lazy[now] = {0,1};
}

int init(int N, int X[], int Y[]) {
    n = N;
    for(int i=0;i<n;i++) a[i] = X[i], b[i] = Y[i];
    build(1,0,n-1);
    for(int i=0;i<n;i++) update(1,0,n-1,i,n-1,(double)log2(a[i]),a[i]);
    for(int i=0;i<n;i++) update(1,0,n-1,i,i,(double)log2(b[i]),b[i]);
	upd(1);
	return tree[1].second;
}

int updateX(int pos, int val) {
    update(1,0,n-1,pos,n-1,-(double)log2(a[pos]),inv(a[pos]));
    a[pos] = val;
	update(1,0,n-1,pos,n-1,(double)log2(a[pos]),a[pos]);
	upd(1);
	return tree[1].second;
}

int updateY(int pos, int val) {
    update(1,0,n-1,pos,pos,-(double)log2(b[pos]),inv(b[pos]));
    b[pos] = val;
	update(1,0,n-1,pos,pos,(double)log2(b[pos]),b[pos]);
	upd(1);
	return tree[1].second;
}

Compilation message (stderr)

horses.cpp: In function 'int init(int, int*, int*)':
horses.cpp:63:17: warning: conversion to 'int' from 'long long int' may alter its value [-Wconversion]
  return tree[1].second;
                 ^
horses.cpp: In function 'int updateX(int, int)':
horses.cpp:71:17: warning: conversion to 'int' from 'long long int' may alter its value [-Wconversion]
  return tree[1].second;
                 ^
horses.cpp: In function 'int updateY(int, int)':
horses.cpp:79:17: warning: conversion to 'int' from 'long long int' may alter its value [-Wconversion]
  return tree[1].second;
                 ^

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