#include <bits/stdc++.h>
#define NM 100010
using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
int tree[4*NM], v[NM],n,m,i,t,x,y;
void build(int nod, int st, int dr) {
    if(st == dr) {
        tree[nod] = v[st];
        return;
    }

    int mij = (st + dr) / 2;
    build(2 * nod, st, mij);
    build(2 * nod + 1, mij + 1, dr);

    tree[nod] =max( tree[2 * nod] , tree[2 * nod + 1]);
}

// modifica nr. de pe pozitia pos in val
void update(int pos, int val, int nod, int st, int dr) {
    // verificam daca intervalul curent e afectat de pos
    if(pos < st || pos > dr) {
        return;
    }
    // daca ne aflam in pos, modificam valuarea
    if(st == dr) {
        tree[nod] = val;
        return;
    }

    // modificam recursiv fiecare jumatate
    int mij = (st + dr) / 2;
    update(pos, val, 2 * nod, st, mij);
    update(pos, val, 2 * nod + 1, mij + 1, dr);

    tree[nod] = max(tree[2 * nod] , tree[2 * nod + 1]);
}

// suma din intervalul [a, b]
int query(int a, int b, int nod, int st, int dr) {
    // [st, dr] nu e inclus in [a, b]
    if(st > b || dr < a) return 0;
    // [st, dr] inclus in [a, b]
    if(a <= st && b >= dr) return tree[nod];

    int mij = (st + dr) / 2;
    int s_st = query(a, b, 2 * nod, st, mij);
    int s_dr = query(a, b, 2 * nod + 1, mij + 1, dr);

    return max(s_st , s_dr);
}
int main()
{
    fin>>n>>m;
    for(i=1; i<=n; i++)
        fin>>v[i];
    build(1,1,n);
    for(i=1; i<=m; i++)
    {
        fin>>t>>x>>y;
        if(t==0)
            fout<<query(1,1,n,x,y)<<'\n';
        else
            update(1,1,n,x,y);
    }
    return 0;
}