//
//  main.c
//  arbint
//
//  Created by Alexandru Bâgu on 12/9/13.
//  Copyright (c) 2013 Alexandru Bâgu. All rights reserved.
//

#include <stdio.h>


int tPow(int);
int update(int, int, int, int*);
void query(int, int, int, int, int, int*, int*);
int max(int,int);


int main(int argc, const char * argv[])
{
    const int MAX_N = 1000001;
    const int MAX_T = (1 << 11) + MAX_N;
    
    freopen("arbint.in", "r", stdin);
    freopen("arbint.out", "w", stdout);
    
    int T[MAX_T], n, m;
    scanf("%d %d", &n, &m);
    int i, treeDepth = tPow(n) + n;
    for(i = 0; i < treeDepth; i++)
        T[i] = 0;
    
    for(i = 1; i <= n; i++)
    {
        int v;
        scanf("%d", &v);
        update(i, v, n, T);
    }
    
    for(i = 0; i < m; i++)
    {
        int a, b, c;
        scanf("%d %d %d", &a, &b, &c);
        if(a == 0)
        {
            int maxim = -1;
            query(1, 1, n, b, c, T, &maxim);
            printf("%d\n", maxim);
        }
        else
        {
            update(b, c, n, T);
        }
    }
    
    return 0;
}

int tPow(int v)
{
    int a = 1;
    while(a < v) a<<=1;
    return 1;
}

int update(int index, int value, int N, int T[])
{
    int n = 1, l = 1, r = N, mid;
    while(l != r)
    {
        mid = (l + r) / 2;
        if(index <= mid)
        {
            r = mid;
            n *= 2;
        }
        else
        {
            l = mid + 1;
            n = n * 2 + 1;
        }
    }
    T[n] = value;
    while(n >= 1)
    {
        n /= 2;
        T[n] = max(T[n * 2], T[n * 2 + 1]);
    }
    return 0;
}
void query(int nod, int left, int right, int start, int finish, int T[], int* maxim)
{
    if ( start <= left && right <= finish )
    {
        if ( *maxim < T[nod] ) *maxim = T[nod];
        return;
    }
    
    int div = (left+right)/2;
    if ( start <= div ) query(2*nod,left,div, start, finish, T, maxim);
    if ( div < finish ) query(2*nod+1,div+1,right, start, finish, T, maxim);
}

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