#include <fstream>
#include <vector>
#define INF 1e9+1
using namespace std;
ifstream cin("arbint.in");
ofstream cout("arbint.out");
int v[200005];
int n,q;
struct arbore {
    vector<long long> tree;
    void init () {
        tree.assign(4*n+4,-INF);
    }
    void build (int node, int l, int r) {
        if (l==r) {
            tree[node]=v[l];
            return;
        }
        int mid=(l+r)/2;
        build(node*2,l,mid);
        build(node*2+1,mid+1,r);
        tree[node]=max(tree[node*2],tree[node*2+1]);
    }
    void pointUpdate(int node, int l, int r, int pos, long long val) {
        if (l==r) {
            tree[node]=val;
            return;
        }
        int mid=(l+r)/2;
        if (pos<=mid) pointUpdate(node*2,l,mid,pos,val);
        else pointUpdate(node*2+1,mid+1,r,pos,val);
        tree[node]=max(tree[node*2],tree[node*2+1]);
    }
    long long rangeQuery(int node, int l, int r, int ql, int qr) {
        if (qr<l || r<ql) {
            return -INF;
        }
        if (ql<=l && r<=qr) {
            return tree[node];
        }
        int mid=(l+r)/2;
        return max(rangeQuery(node*2,l,mid,ql,qr),rangeQuery(node*2+1,mid+1,r,ql,qr));
    }
};
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cin>>n>>q;
    for (int i=1; i<=n; ++i) cin>>v[i];
    arbore st;
    st.init();
    st.build(1,1,n);
    while (q--) {
        int type;
        cin>>type;
        if (type==1) {
            int pos;
            long long x;
            cin>>pos>>x;
            st.pointUpdate(1,1,n,pos,x);
        }
        else if (type==0) {
            int l, r;
            cin>>l>>r;
            cout<<st.rangeQuery(1,1,n,l,r)<<'\n';
        }
    }
}