#include <bits/stdc++.h>
#define NMAX 100005
using namespace std;
int arb[4*NMAX + 55], maxx;
void update(int nod, int st, int dr, int poz, int val){
    if(st == dr){
        arb[nod] = val;
        return;
    }
    int mid = (st + dr) / 2;
    if(poz <= mid) update(2*nod, st, mid, poz, val);
    else if(poz > mid) update(2*nod+1, mid+1, dr, poz, val);
    arb[nod] = max(arb[2*nod], arb[2*nod+1]);
}
void query(int nod, int st, int dr, int x, int y){
    if(x <= st && dr <= y){
        maxx = max(maxx, arb[nod]);
        return;
    }
    int mid = (st + dr) / 2;
    if(x <= mid) query(2*nod, st, mid, x, y);
    if(y > mid) query(2*nod+1, mid+1, dr, x, y);
}
int main(){
    ifstream in("arbint.in");
    ofstream out("arbint.out");
    int n, q, a, t, x, y;
    in >> n >> q;
    for(int i = 1; i <= n; i++){
        in >> a;
        update(1, 1, n, i, a);
    }
    for(int i = 1; i <= q; i++){
        in >> t >> x >> y;
        if(t == 1){
            update(1, 1, n, x, y);
        }
        else{
            maxx = 0;
            query(1, 1, n, x, y);
            out << maxx << endl;
        }
    }
}