#include <bits/stdc++.h>
#define pb push_back

using namespace std;

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

void debug_out() { cerr << '\n'; }
template <typename Head, typename... Tail> void debug_out(Head H, Tail... T) { cerr << " " << H; debug_out(T...);}
#define dbg(...) cerr << #__VA_ARGS__ << " ->", debug_out(__VA_ARGS__)
#define dbg_v(x, n) do{cerr<<#x"[]: ";for(int _=0;_<n;++_)cerr<<x[_]<<" ";cerr<<'\n';}while(0)
#define dbg_ok cerr<<"OK!\n"

typedef pair<int,int> pii;
typedef long long int ll;
typedef long double ld;

const int DMAX = 1e5+10;

int V[DMAX];
int tree[4*DMAX];

int n,m;

void build(int node,int st,int dr);
void update(int node,int st,int dr,int pos,int val);
int query(int node,int st,int dr,int x,int y);

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    int t,i,j;
    int x,y,z;

    fin>>n>>m;
    for(i=1;i<=n;i++)
        fin>>V[i];
    build(1,1,n);
    while(m--){
        fin>>x>>y>>z;
        if(x & 1)
            update(1,1,n,y,z);
        else
            fout<<query(1,1,n,y,z)<<'\n';
    }

    return 0;
}
void build(int node,int st,int dr){
    if(st == dr){
        tree[node]=V[st];
        return;
    }
    int mij=(st+dr)/2;
    build(2*node,st,mij);
    build(2*node+1,mij+1,dr);
    tree[node]=max(tree[2*node],tree[2*node+1]);
}
void update(int node,int st,int dr,int pos,int val){
    if(st == dr){
        tree[node]=val;
        return;
    }
    int mij=(st+dr)/2;
    if(pos <= mij)
        update(2*node,st,mij,pos,val);
    else
        update(2*node+1,mij+1,dr,pos,val);
    tree[node]=max(tree[2*node],tree[2*node+1]);
}
int query(int node,int st,int dr,int x,int y){
    if(x <= st && dr <= y)
        return tree[node];
    int mij=(st+dr)/2;
    int ans=0;
    if(x <= mij)
        ans=query(2*node,st,mij,x,y);
    if(y > mij)
        ans=max(ans,query(2*node+1,mij+1,dr,x,y));
    return ans;
}