Cod sursa(job #147865)

Utilizator the1dragonIonita Alexandru the1dragon Data 3 martie 2008 17:37:23
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.24 kb
#include<stdio.h>
#define MAX 102400

int v[3*MAX];

int max(int a, int b)
{
	if (a>=b) return a;
	return b;
}

void update(int poz)
{
	if (poz>0)
	{
		v[poz]=max(v[poz*2], v[poz*2+1]);
		update(poz/2);
	}
	return;
}

void adauga(int val, int unde, int poz, int st, int dr)
{

	if ((st==unde)&&(unde==dr))
	{	
		v[poz]=val;
		update(poz/2);
		return;
	}
	
	if ((st<=unde)&&(unde<=dr))
	{
		adauga(val, unde, poz*2, st, (st+dr)/2);
		adauga(val, unde, poz*2+1, (st+dr)/2+1, dr);
	}
	return;

}
int afla(int L, int R, int poz, int st, int dr)
{
	
	if ((L>dr)||(R<st))
		return 0;
	if ((L<=st)&&(R>=dr))
		return v[poz];
	
	return max(afla(L, R, poz*2, st, (st+dr)/2), afla(L, R, poz*2+1, (st+dr)/2+1, dr));
}

int main()
{
	freopen("arbint.in", "r", stdin);
	freopen("arbint.out", "w", stdout);
	
	int n, m, a, b, c, i;
	
	scanf("%d %d", &n, &m);
	for (i=1; i<=n; i++)
	{
		scanf("%d", &a);
		//val lui i va deveni a
		adauga(a, i, 1, 1, n);
	}
	
	for (i=1; i<=m; i++)
	{
		scanf("%d %d %d", &a, &b, &c);
		if (a==0)
		{
			//max pe intervalul b c
			printf("%d\n", afla(b, c, 1, 1, n));
		}
		else
		{
			//val lui b va deveni c
			adauga(c, b, 1, 1, n);
		}
	}
	fclose(stdout);
	return 0;
}