#include<bits/stdc++.h>
using namespace std;
#define INIT  ios_base :: sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define mp make_pair
#define pb push_back
#define ft first
#define sc second
#define ll long long
#define pii pair<int, int>
#define count_bits __builtin_popcount
#define int ll


int n, m;
int a[100010];

ifstream fin("arbint.in"); ofstream fout("arbint.out");
#define cin fin
#define cout fout


int tree[400010];


void build(int v, int l, int r){
if(l==r){
    tree[v]=a[l];
    return;
}
int mid=(l+r)>>1ll;
build(2*v, l, mid); build(2*v+1, mid+1, r);
tree[v]=max(tree[2*v], tree[2*v+1]);
return;
}


void update(int v, int l, int r, int p, int x){

if(l==r){
    a[p]=x;
    tree[v]=a[p];
    return;
}
int mid=(l+r)>>1ll;
if(p<=mid){
    update(2*v, l, mid, p, x);
}
else{
    update(2*v+1, mid+1, r, p , x);
}

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


int query(int v, int tl, int tr, int l, int r){

if(l>r){
    return -1;
}

if( (tl==l) && (tr==r) ){
    return tree[v];
}

int mid=(tl+tr)>>1ll;

return max( query(2*v, tl, mid, l, min(r, mid)), query(2*v+1, mid+1, tr, max(l, mid+1), r)  );
}


int32_t main(){
INIT
cin>>n>>m;
for(int i=1; i<=n; i++){
    cin>>a[i];
}
build(1, 1, n);

for(int qr=1; qr<=m; qr++){
    int tp;
    cin>>tp;
    if(tp==0){
        int l, r;
        cin>>l>>r;
        cout<<query(1, 1, n, l, r)<<"\n";
    }
    else{
        int p, x;
        cin>>p>>x;
        update(1, 1, n, p, x);
    }
}




return 0;
}