Submission #225769

#	Time	Username	Problem	Language	Result	Execution time	Memory
225769		staniewzki	Horses (IOI15_horses)	C++17	100 / 100	254 ms	42488 KiB

horses

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

#define REP(i, n) for(int i = 0; i < n; i++)
 
#include "horses.h"

struct Node {
	int x, y;
	double _x, _y;
};

const int mod = int(1e9 + 7);
int mul(int a, int b) {
	return (long long) a * b % mod;
}

Node operator+(Node &a, Node &b) {
	Node ret;
	if(a._y > a._x + b._y) {
		ret.y = a.y;
		ret._y = a._y;
	}
	else {
		ret.y = mul(a.x, b.y);
		ret._y = a._x + b._y;
	}

	ret.x = mul(a.x, b.x);
	ret._x = a._x + b._x;
	return ret;
};

struct Tree {
	vector<Node> tree;
	int sz = 1;

	Tree(int n = 0) {
		while(sz < n) sz *= 2;
		tree.resize(sz * 2);
	}

	void update(int pos) {
		pos += sz;
		tree[pos]._x = log2(tree[pos].x);
		tree[pos]._y = log2(tree[pos].y);
		while(pos /= 2)
			tree[pos] = tree[pos * 2] + tree[pos * 2 + 1];
	}

	Node& operator[](int pos) { return tree[pos + sz]; }
	int query() { return tree[1].y; }
} tree;

int init(int N, int X[], int Y[]) {
	tree = Tree(N + 1);
	REP(i, N) {
		tree[i].x = X[i];
		tree[i + 1].y = Y[i];
	}
	REP(i, N + 1) tree.update(i);
	return tree.query();
}

int updateX(int pos, int val) {	
	tree[pos].x = val;
	tree.update(pos);
	return tree.query();
}

int updateY(int pos, int val) {
	tree[++pos].y = val;
	tree.update(pos);
	return tree.query();
}

Compilation message (stderr)

horses.cpp: In function 'int mul(int, int)':
horses.cpp:15:27: warning: conversion to 'int' from 'long long int' may alter its value [-Wconversion]
  return (long long) a * b % mod;
         ~~~~~~~~~~~~~~~~~~^~~~~

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