Submission #778251

#	Time	Username	Problem	Language	Result	Execution time	Memory
778251		danikoynov	Horses (IOI15_horses)	C++14	20 / 100	533 ms	52908 KiB

horses

#include "horses.h"
#include<bits/stdc++.h>

using namespace std;
typedef long long ll;

const int maxn = 5e5 + 10;
const ll mod = 1e9 + 7;
ll x[maxn], y[maxn], n;

ll prod_tree[4 * maxn];

void build_prod_tree(int root, int left, int right)
{
    if (left == right)
    {
        prod_tree[root] = x[left];
        return;
    }

    int mid = (left + right) / 2;
    build_prod_tree(root * 2, left, mid);
    build_prod_tree(root * 2 + 1, mid + 1, right);

    prod_tree[root] = (prod_tree[root * 2] * prod_tree[root * 2 + 1]) % mod;
}

void update_prod(int root, int left, int right, int pos)
{
    if (left == right)
    {
        prod_tree[root] = x[left];
        return;
    }

    int mid = (left + right) / 2;
    if (pos <= mid)
        update_prod(root * 2, left, mid, pos);
    else
        update_prod(root * 2 + 1, mid + 1, right, pos);

    prod_tree[root] = (prod_tree[root * 2] * prod_tree[root * 2 + 1]) % mod;
}

ll prod_query(int root, int left, int right, int qleft, int qright)
{
    if (left > qright || right < qleft)
        return 1;
    if (left >= qleft && right <= qright)
        return prod_tree[root];

    int mid = (left + right) / 2;
    return (prod_query(root * 2, left, mid, qleft, qright) *
            prod_query(root * 2 + 1, mid + 1, right, qleft, qright)) % mod;
}

ll breed_tree[4 * maxn];

void build_breed_tree(int root, int left, int right)
{
    if (left == right)
    {
        breed_tree[root] = y[left];
        return;
    }

    int mid = (left + right) / 2;
    build_breed_tree(root * 2, left, mid);
    build_breed_tree(root * 2 + 1, mid + 1, right);

    breed_tree[root] = max(breed_tree[root * 2], breed_tree[root * 2 + 1]);
}

void update_breed(int root, int left, int right, int pos)
{
    if (left == right)
    {
        breed_tree[root] = y[left];
        return;
    }

    int mid = (left + right) / 2;
    if (pos <= mid)
        update_breed(root * 2, left, mid, pos);
    else
        update_breed(root * 2 + 1, mid + 1, right, pos);

    breed_tree[root] = max(breed_tree[root * 2], breed_tree[root * 2 + 1]);
}

ll breed_query(int root, int left, int right, int qleft, int qright)
{
    if (left > qright || right < qleft)
        return 0;

    if (left >= qleft && right <= qright)
        return breed_tree[root];

    int mid = (left + right) / 2;
    return max(breed_query(root * 2, left, mid, qleft, qright),
               breed_query(root * 2 + 1, mid + 1, right, qleft, qright));
}

set < int > active;

ll action()
{
    ll up = y[n - 1], dw = 1, pos = n - 1;
    ll div = 1;
    set < int > :: reverse_iterator it;

    for (it = active.rbegin(); it != active.rend(); it ++)
    {
        ll cur = breed_query(1, 0, n - 1, *it, n - 1);
        if (div > 1e9)
            break;
            ///cout << *it << " " << cur << " " << div << endl;
        if (cur * dw >= up * div)
        {
            up = cur;
            dw = div;
            pos = *it;
        }
        div = div * x[*it];
    }

    /**for (int i = n - 2; i >= 0; i --)
    {
        div = div * x[i + 1];
        if (div > 1e9)
            break;
        ///cout << i << " : " << y[i] << " " << div << endl;
        /// y[i] / div >? up / dw
        if (y[i] * dw >= up * div)
        {

            ///cout << " " << up << " : " << dw << endl;
            up = y[i];
            dw = div;
            pos = i;
        }
    }*/

    ///cout << pos << endl;
    ll ans = prod_query(1, 0, n - 1, 0, pos);
    //for (int i = 0; i <= pos; i ++)
    //  ans = (ans * x[i]) % mod;
    ans = (ans * breed_query(1, 0, n - 1, pos, n - 1)) % mod;
    return ans;
}
int init(int N, int X[], int Y[])
{
    n = N;
    for (int i = 0; i < n; i ++)
    {
        if (X[i] > 1)
            active.insert(i);
        x[i] = X[i];
        y[i] = Y[i];
    }
    build_prod_tree(1, 0, n - 1);
    build_breed_tree(1, 0, n - 1);
    return action();
}

int updateX(int pos, int val)
{
    if (x[pos] > 1)
        active.erase(pos);
    x[pos] = val;
    if (x[pos] > 1)
        active.insert(pos);
    update_prod(1, 0, n - 1, pos);
    return action();
}

int updateY(int pos, int val)
{
    y[pos] = val;
    update_breed(1, 0, n - 1, pos);
    return action();
}

Compilation message (stderr)

horses.cpp: In function 'll action()':
horses.cpp:114:38: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  114 |         ll cur = breed_query(1, 0, n - 1, *it, n - 1);
      |                                    ~~^~~
horses.cpp:114:50: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  114 |         ll cur = breed_query(1, 0, n - 1, *it, n - 1);
      |                                                ~~^~~
horses.cpp:115:13: warning: conversion from 'll' {aka 'long long int'} to 'double' may change value [-Wconversion]
  115 |         if (div > 1e9)
      |             ^~~
horses.cpp:145:33: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  145 |     ll ans = prod_query(1, 0, n - 1, 0, pos);
      |                               ~~^~~
horses.cpp:145:41: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  145 |     ll ans = prod_query(1, 0, n - 1, 0, pos);
      |                                         ^~~
horses.cpp:148:38: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  148 |     ans = (ans * breed_query(1, 0, n - 1, pos, n - 1)) % mod;
      |                                    ~~^~~
horses.cpp:148:43: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  148 |     ans = (ans * breed_query(1, 0, n - 1, pos, n - 1)) % mod;
      |                                           ^~~
horses.cpp:148:50: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  148 |     ans = (ans * breed_query(1, 0, n - 1, pos, n - 1)) % mod;
      |                                                ~~^~~
horses.cpp: In function 'int init(int, int*, int*)':
horses.cpp:161:29: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  161 |     build_prod_tree(1, 0, n - 1);
      |                           ~~^~~
horses.cpp:162:30: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  162 |     build_breed_tree(1, 0, n - 1);
      |                            ~~^~~
horses.cpp:163:18: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  163 |     return action();
      |            ~~~~~~^~
horses.cpp: In function 'int updateX(int, int)':
horses.cpp:173:25: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  173 |     update_prod(1, 0, n - 1, pos);
      |                       ~~^~~
horses.cpp:174:18: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  174 |     return action();
      |            ~~~~~~^~
horses.cpp: In function 'int updateY(int, int)':
horses.cpp:180:26: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  180 |     update_breed(1, 0, n - 1, pos);
      |                        ~~^~~
horses.cpp:181:18: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
  181 |     return action();
      |            ~~~~~~^~

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