// Arbori de intervale.cpp : Defines the entry point for the console application.
//

//#include "stdafx.h"
#include "stdio.h"

FILE *f=fopen("arbint.in", "r");
FILE *g=fopen("arbint.out", "w");

typedef struct arbore
{
	int x, y;
};

arbore arb[1000001];

int n, v[100001], m, imax;
int poz[100001];
int w[1000001];
int maxaf=0;


int maxim(int x, int y)
{
	 if (x>y) return x;
	 return y;
}

void read()
{
	fscanf(f, "%d%d", &n, &m);
	for (int i=1; i<=n; ++i)
		fscanf(f, "%d", &v[i]);
}


void init(int x, int y, int i)
{
	if (i>imax) imax=i;
	arb[i].x=x;
	arb[i].y=y;
	int mid=(x+y)/2;
	if (x<=mid && x!=y)
		init(x, mid, i*2);
	if (y>mid)
		init (mid+1, y, i*2+1);
}


void init2()
{
	for (int j=imax; j>=1; --j)
	{
		if (arb[j].x==arb[j].y)
		{
			w[j]=v[arb[j].x];
			poz[arb[j].x]=j;
		}
		else
			w[j]=maxim(w[j*2], w[j*2+1]);
	}
}


void uparb(int x)
{
	int t=x/2;
	while (t>0)
	{
		w[t]=maxim(w[t*2], w[t*2+1]);
		t=t/2;
	}
}


void actualizare(int nod, int st, int dr, int a, int b)
{
	if (a<=st && b>=dr) 
		maxaf=maxim(maxaf, w[nod]);
	else
	{
		int mid=(st+dr)/2;
		if (st<=mid && st!=dr)
			actualizare(nod*2, st, mid, a, b);
		if (dr>mid)
			actualizare(nod*2+1, mid+1, dr, a, b);
	}
}



void program()
{
	for (int j=1; j<=m; ++j)
	{
		int x, a, b;
		fscanf(f, "%d%d%d", &x, &a, &b);
		if (x==1)
		{
			w[poz[a]]=b;
			uparb(poz[a]);
		}
		else
		{
			maxaf=-1;
			actualizare(1, 1, n, a, b);
			fprintf(g, "%d\n", maxaf);
		}
	}
}


int main()
{
	read();
	init(1, n, 1);
	init2();
	program();
	return 0;
}