Submission #233883

#	Time	Username	Problem	Language	Result	Execution time	Memory
233883		triple_fault	Horses (IOI15_horses)	C++14	17 / 100	81 ms	56584 KiB

horses

#include "horses.h"
#include <vector>
#include <algorithm>
#include <cstdio>

#define MAX 500001
typedef int64_t ll;

ll MOD = 1e9 + 7;
using namespace std;

ll seg[4 * MAX];
vector<pair<ll, ll>> lazy(4 * MAX, {1, 1});

ll n;
ll pp[MAX];
ll y[MAX];
ll x[MAX];

void build(ll v, ll tl, ll tr) {
    if (tl == tr) seg[v] = pp[tl] * y[tr];
    else {
        ll mid = (tl + tr) / 2;
        build(v * 2, tl, mid);
        build((v * 2) + 1, mid + 1, tr);
        seg[v] = max(seg[v * 2], seg[(v * 2) + 1]);
    }
}

void push(ll v) {
    if (lazy[v].first != 1 || lazy[v].second != 1) {
        ll f = lazy[v].first, s = lazy[v].second;
        lazy[v * 2].first *= f; lazy[v * 2].second *= s;
        lazy[(v * 2) + 1].first *= f; lazy[(v * 2) + 1].second *= s;
        lazy[v] = {1, 1};
        seg[v * 2] *= f; seg[v * 2] /= s;
        seg[(v * 2) + 1] *= f; seg[(v * 2) + 1] /= s;
    }
}

void update(ll numer, ll denom, ll v, ll l, ll r, ll tl, ll tr) {
    if (l > r) return;
    if (tl == l && tr == r) {
        lazy[v].first *= numer;
        lazy[v].second *= denom;
        seg[v] /= denom;
        seg[v] *= numer;
        return;
    }
    push(v);
    ll mid = (tl + tr) / 2;
    update(numer, denom, v * 2, l, min(r, mid), tl, mid);
    update(numer, denom, (v * 2) + 1, max(l, mid + 1), r, mid + 1, tr);
    seg[v] = max(seg[v * 2], seg[(v * 2) + 1]);
}

void update_specific(ll v, ll idx, ll l, ll r, ll nw) {
    if (l > r) return;
    if (l == idx && r == idx) {
        seg[v] /= y[idx];
        seg[v] *= nw;
        return;
    }
    push(v);
    ll mid = (l + r) / 2;
    if (idx <= mid) update_specific(v * 2, idx, l, mid, nw);
    else update_specific((v * 2) + 1, idx, mid + 1, r, nw);
    seg[v] = max(seg[v * 2], seg[(v * 2) + 1]);
}

int init(int N, int X[], int Y[]) {
    n = (ll)N;
    for (ll i = 0; i < n; ++i) y[i] = (ll)Y[i];
    for (ll i = 0; i < n; ++i) x[i] = (ll)X[i];

    pp[0] = x[0];
    for (ll i = 1; i < n; ++i) pp[i] = pp[i - 1] * x[i];

    build(1, 0, n - 1);
	return seg[1] % MOD;
}

int updateX(int pos, int val) {	
    update((ll)val, x[pos], 1, (ll)pos, n - 1, 0, n - 1);
    x[pos] = (ll)val;
	return seg[1] % MOD;
}

int updateY(int pos, int val) {
    update_specific(1, (ll)pos, 0, n - 1, val);
    y[pos] = (ll)val;
	return seg[1] % MOD;
}

Compilation message (stderr)

horses.cpp: In function 'int init(int, int*, int*)':
horses.cpp:80:16: warning: conversion to 'int' from 'll {aka long int}' may alter its value [-Wconversion]
  return seg[1] % MOD;
         ~~~~~~~^~~~~
horses.cpp: In function 'int updateX(int, int)':
horses.cpp:86:16: warning: conversion to 'int' from 'll {aka long int}' may alter its value [-Wconversion]
  return seg[1] % MOD;
         ~~~~~~~^~~~~
horses.cpp: In function 'int updateY(int, int)':
horses.cpp:92:16: warning: conversion to 'int' from 'll {aka long int}' may alter its value [-Wconversion]
  return seg[1] % MOD;
         ~~~~~~~^~~~~

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