Cod sursa(job #829259)

Utilizator BalcauIonutFMI-Balcau Ionut BalcauIonut Data 4 decembrie 2012 23:12:08
Problema Arbori de intervale Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.89 kb
#include<cstdio>
#define max(x,y) ((x)>(y))?(x):(y)
int a[400000];

void update(int nod,int left, int right, int &val, int &pos){
	if(left==right){
			a[nod]=val;
			return;
		}
	int mij=(left+right)/2;
	if(pos<=mij)
		update(nod*2,left,mij,val,pos);
	else
		update(nod*2+1,mij+1,right,val,pos);
	a[nod]=max(a[nod*2],a[nod*2+1]);
}

int query(int nod,int left, int right,int &l, int &r){
	if(l<=left && r>=right){
		return a[nod];
	}
	int mij=(left+right)/2;
	return max( l<=mij?query(nod*2,left,mij,l,r):0 , r>mij?query(nod*2+1,mij+1,right,l,r):0 );
}

int main(){
	int n,m,x,i;
	freopen("arbint.in","r",stdin);
	freopen("arbint.out","w",stdout);
	scanf("%d%d",&n,&m);
	for(i=1;i<=n;++i){
		scanf("%d",&x);
		update(1,1,n,x,i);
	}
	int t,y;
	for(;m>0;--m){
		scanf("%d%d%d",&t,&x,&y);
		if(t) update(1,1,n,y,x);
		else printf("%d\n",query(1,1,n,x,y));		
	}
	return 0;
}