#include<cstdio>
#include<fstream>
#include<iostream>
#include<iomanip>
#include<algorithm>
#include<vector>
#include<bitset>
#include<deque>
#include<queue>
#include<set>
#include<map>
#include<cmath>
#include<cstring>
#include<ctime>
#include<cstdlib>
#include<unordered_map>

#define ll long long
#define pb push_back
#define mp make_pair
#define pii pair<int,int>
#define pll pair<ll,ll>
#define all(x) (x).begin(), (x).end()
#define fi first
#define se second

using namespace std;

const int nmax = 100005;

int n, q, i, op, a, b, poz, val, sol, v[nmax], seg[4 * nmax];

void build(int node, int l, int r)
{
    if(l == r)
    {
        seg[node] = v[l];
        return;
    }

    int m = (l + r) / 2;
    int ls = 2 * node;
    int rs = 2 * node + 1;

    build(ls, l, m);
    build(rs, m + 1, r);

    seg[node] = max(seg[ls], seg[rs]);
}

void update(int node, int l, int r, int poz, int val)
{
    if(l == r)
    {
        seg[node] = val;
        return;
    }

    int m = (l + r) / 2;
    int ls = 2 * node;
    int rs = 2 * node + 1;

    if(poz <= m) update(ls, l, m, poz, val);
    else update(rs, m + 1, r, poz, val);

    seg[node] = max(seg[ls], seg[rs]);
}

void query(int node, int l, int r, int a, int b)
{
    if(l >= a && r <= b)
    {
        sol = max(sol, seg[node]);
        return;
    }

    int m = (l + r) / 2;
    int ls = 2 * node;
    int rs = 2 * node + 1;

    if(a <= m) query(ls, l, m, a, b);
    if(b > m) query(rs, m + 1, r, a, b);
}

int main()
{
    freopen("arbint.in", "r", stdin);
    freopen("arbint.out", "w", stdout);

    scanf("%d%d", &n, &q);

    for(i = 1; i <= n; i++)
        scanf("%d", &v[i]);

    build(1, 1, n);

    for(; q; q--)
    {
        scanf("%d", &op);

        if(op == 1)
        {
            scanf("%d%d", &poz, &val);
            update(1, 1, n, poz, val);
        }
        else
        {
            scanf("%d%d", &a, &b);
            sol = 0;
            query(1, 1, n, a, b);
            printf("%d\n", sol);
        }
    }

    return 0;
}