Cod sursa(job #1248216)

Utilizator dan.marculetFII MarculetDan dan.marculet Data 24 octombrie 2014 19:42:32
Problema Arbori de intervale Scor 0
Compilator c Status done
Runda Arhiva educationala Marime 1.41 kb
#include <stdio.h>
#include <fstream>
#include <assert.h> 
using namespace std;

#define in "arbint.in"
#define out "arbint.out"
#define dim 100001

int N, M;
int MaxArb[4 * dim + 66];
int start, finish, Val, Pos, maxim;

inline int Maxim(int a, int b) {
	if (a > b) return a;
	return b;
}

void Update(int, int, int);
void Query(int, int, int);

int main()
{
	int X, A, B;
	freopen(in, "r", stdin);
	freopen(out, "w", stdout);

	scanf("%d%d", &N, &M);
	for (int i = 1; i <= N; i++)
	{
		scanf("%d", &X);
		Pos = i, Val = X;
		Update(1, 1, N);
	}

	for (int i = 1; i <= M; i++)
	{
		scanf("%d%d%d", &X, &A, &B);
		if (X == 0)
		{
			maxim = -1;
			start = A, finish = B;
			Query(1, 1, N);

			printf("%d\n", maxim);
		}
		else
		{
			Pos = A, Val = B;
			Update(1, 1, N);
		}
	}
}

void Update(int nod, int left, int right)
{
	if (left == right)
	{
		MaxArb[nod] = Val;
		return;
	}

	int div = (left + right) / 2;
	if (Pos <= div) Update(2 * nod, left, div);
	else              Update(2 * nod + 1, div + 1, right);

	MaxArb[nod] = Maxim(MaxArb[2 * nod], MaxArb[2 * nod + 1]);
}

void Query(int nod, int left, int right)
{
	if (start <= left && right <= finish)
	{
		if (maxim < MaxArb[nod]) maxim = MaxArb[nod];
		return;
	}

	int div = (left + right) / 2;
	if (start <= div) Query(2 * nod, left, div);
	if (div < finish) Query(2 * nod + 1, div + 1, right);
}