#include<stdio.h>
#define Nmax 100005
FILE*f=fopen("arbint.in","r");
FILE*g=fopen("arbint.out","w");

int poz,Rez,a,b,X,q1,q2,M,N,i,t,A[4*Nmax];

void update(int nod,int st,int dr){
	if ( st == dr ){
		A[nod] = X;
		return ;
	}
	int nodst = (nod << 1);
	int noddr = nodst + 1;
	int mj = st + ( dr - st ) / 2;
	
	if ( poz <= mj ){
		update(nodst,st,mj);
	}
	else{
		update(noddr,mj+1,dr);
	}
	A[nod] = A[nodst] > A[noddr] ? A[nodst] : A[noddr]; 
}

void query(int nod,int st,int dr){
	if ( a <= st && dr <= b ){
		if ( Rez < A[nod] )
			Rez = A[nod];
		return ;
	}
	int nodst = nod << 1;
	int noddr = nodst + 1;
	int mj = st + ( dr - st ) / 2;
	if ( a <= mj ){
		query(nodst,st,mj);
	}
	if ( b > mj ){
		query(noddr,mj + 1,dr);
	}
	
}

int main () {
	fscanf(f,"%d %d",&N,&M);
	
	for ( i = 1 ; i <= N ; ++i ){
		poz = i;
		fscanf(f,"%d",&X);
		update(1,1,N);
	}
	
	for ( i = 1 ; i <= M ; ++i ){
		fscanf(f,"%d %d %d",&t,&q1,&q2);
		if ( t ){
			poz = q1; X = q2;
			update(1,1,N);
		}
		else{
			a = q1; b = q2;
			Rez = -1;
			query(1,1,N);
			fprintf(g,"%d\n",Rez);
		}
	}
	
	
	fclose(f);
	fclose(g);
	
	return 0;
}