Submission #726494

#	Time	Username	Problem	Language	Result	Execution time	Memory
726494		becaido	Horses (IOI15_horses)	C++17	17 / 100	144 ms	44292 KiB

horses

#include <bits/stdc++.h>
#include "horses.h"
using namespace std;

#define lpos pos*2
#define rpos pos*2+1

const int MOD = 1e9 + 7;
const int SIZE = 5e5 + 5;

struct Node {
    int pro = 1;
    double sum = 0, mx = 0;
    Node operator + (const Node& rhs) const {
        Node re;
        re.pro = 1ll * pro * rhs.pro % MOD;
        re.sum = sum + rhs.sum;
        re.mx = max(mx, sum + rhs.mx);
        return re;
    }
} node[4 * SIZE];

int n, y[SIZE];

void upd(int pos, int l, int r, int p, int ty, int x) {
    if (l == r) {
        if (ty == 1) {
            node[pos].pro = x;
            node[pos].sum = log(x);
        }
        if (ty == 2) {
            node[pos].mx = node[pos].sum + log(y[p] = x);
        }
        return;
    }
    int mid = (l + r) / 2;
    if (p <= mid) upd(lpos, l, mid, p, ty, x);
    else upd(rpos, mid + 1, r, p, ty, x);
    node[pos] = node[lpos] + node[rpos];
}

int que(int pos, int l, int r, int cur = 1) {
    if (l == r) return 1ll * cur * node[pos].pro % MOD * y[l] % MOD;
    int mid = (l + r) / 2;
    if (node[lpos].mx >= node[lpos].sum + node[rpos].mx) return que(lpos, l, mid, cur);
    else return que(rpos, mid + 1, r, 1ll * cur * node[lpos].pro % MOD);
}

int init(int N, int X[], int Y[]) {
    auto build = [&](auto build, int pos, int l, int r)->void {
        if (l == r) {
            node[pos].pro = X[l];
            node[pos].sum = log(X[l]);
            node[pos].mx = node[pos].sum + log(y[l] = Y[l]);
            return;
        }
        int mid = (l + r) / 2;
        build(build, lpos, l, mid);
        build(build, rpos, mid + 1, r);
        node[pos] = node[lpos] + node[rpos];
    };
    n = N;
    build(build, 1, 0, n - 1);
    return que(1, 0, n - 1);
}

int updateX(int pos, int val) {
    upd(1, 0, n - 1, pos, 1, val);
    return que(1, 0, n - 1);
}

int updateY(int pos, int val) {
    upd(1, 0, n - 1, pos, 2, val);
    return que(1, 0, n - 1);
}

Compilation message (stderr)

horses.cpp: In member function 'Node Node::operator+(const Node&) const':
horses.cpp:16:38: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   16 |         re.pro = 1ll * pro * rhs.pro % MOD;
      |                  ~~~~~~~~~~~~~~~~~~~~^~~~~
horses.cpp: In function 'int que(int, int, int, int)':
horses.cpp:43:63: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   43 |     if (l == r) return 1ll * cur * node[pos].pro % MOD * y[l] % MOD;
      |                        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~
horses.cpp:46:66: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
   46 |     else return que(rpos, mid + 1, r, 1ll * cur * node[lpos].pro % MOD);
      |                                       ~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~
horses.cpp: In lambda function:
horses.cpp:50:27: warning: declaration of 'build' shadows a previous local [-Wshadow]
   50 |     auto build = [&](auto build, int pos, int l, int r)->void {
      |                      ~~~~~^~~~~
horses.cpp:50:10: note: shadowed declaration is here
   50 |     auto build = [&](auto build, int pos, int l, int r)->void {
      |          ^~~~~

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