#include <bits/stdc++.h>

using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");

int aint[2000001];
int arr[2000001];
int n_nodes, n_query;

void build(int node, int left, int right){
    if(left == right)
        aint[node] = arr[left];
    else{
        int mid = (left+right)/2;
        build(node*2, left, mid);
        build(node*2 + 1, mid + 1, right);
        aint[node] = max(aint[node*2], aint[node*2 + 1]);
    }
}
void update(int node, int left, int right, int pos, int val_new){
    if(left == right)
        aint[node] = val_new;
    else{
        int mid = (left+right)/2;
        if(pos <= mid)
            update(node*2, left, mid, pos, val_new);
        if(pos > mid)
            update(node*2 + 1, mid + 1, right, pos, val_new);
        aint[node] = max(aint[node*2], aint[node*2+1]);
    }
}
int query(int node, int left, int right, int query_left, int query_right){
    if(query_left <= left && right <= query_right)
        return aint[node];
    else{
        int mid = (left + right) / 2;
        if(mid >= query_right)
            return query(node*2, left, mid, query_left, query_right);
        if(mid + 1 <= query_left)
            return query(node*2 + 1, mid + 1, right, query_left, query_right);

        return max(query(node*2, left, mid, query_left, query_right), query(node*2 + 1, mid + 1, right, query_left, query_right));

    }
}


int main()
{
    fin>>n_nodes>>n_query;
    int x,y,z;
    for(int i = 1; i<=n_nodes; i++){
        fin>>x;
        arr[i] = x;
    }
    build(1,1,n_nodes);
    for(int i = 1; i<=n_query; i++){
        fin>>x>>y>>z;
        //cout<<x<<' '<<y<<' '<<z<<endl;
        if(x)
            update(1, 1, n_nodes, y, z);
        else
            fout<<query(1, 1, n_nodes, y, z)<<'\n';

    }
    return 0;
}