#include <iostream>
#include <fstream>
#include <vector>
using namespace std;

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

struct ST{
    // [1-indexed]
    // [uses <vector>, <algorithm>]

    int N;
    vector <int> T;

    ST(int Size) : N(Size) { // Constructor
        T.resize(4 * N + 1, 0);
    }

    void Update(int node, int from, int to, int pos, int val){ // Adds a value to a specified place whitin the ST
        if(from == to){
            T[node] = val;
            return;
        }
        int mid = (from + to) / 2;
        if(pos <= mid)
            Update(2 * node, from, mid, pos, val);
        else
            Update(2 * node + 1, mid + 1, to, pos, val);
        T[node] = max(T[2 * node], T[2 * node + 1]);
    }
    int Query(int node, int from, int to, int qleft, int qright){ // Returns the sum between two places
        if(qleft <= from && to <= qright)
            return T[node];

        int mid = (from + to) / 2, smax = 0;

        if(qleft <= mid){
            int s = Query(2 * node, from, mid, qleft, qright);
            smax = max(s, smax);
        }
        if(qright > mid){
            int s = Query(2 * node + 1, mid + 1, to, qleft, qright);
            smax = max(s, smax);
        }

        return smax;
    }
};

int main(){

    int N, M, val;
    fin >> N >> M;

    ST st(N);

    for(int i = 1; i <= N; i ++){
        fin >> val;
        st.Update(1, 1, N, i, val);
    }

    int op, x, y;
    for(int i = 1; i <= M; i ++){
        fin >> op >> x >> y;
        if(op == 1)
            st.Update(1, 1, N, x, y);
        else
            fout << st.Query(1, 1, N, x, y) << '\n';
    }


    return 0;
}