///INTERVAL TREE
#include <fstream>
#include <vector>
#include <cstdlib>

using namespace std;

struct Node {
    int val = -1;
    Node* left = NULL;
    Node* right = NULL;
};

void updateTree(Node* node, int A, int B, const int i, const int val) {
    if(A == B) {
        node -> val = val;
    } else {
        int M = (A+B)/2;
        if(i<=M) {
            if(node -> left == NULL) {
                node -> left = new Node;
            }
            updateTree(node -> left, A, M, i, val);
        } else {
            if(node -> right == NULL) {
                node -> right = new Node;
            }
            updateTree(node -> right, M+1, B, i, val);
        }
        if(node -> left != NULL) {
            node -> val = node -> left -> val;
            if(node -> right != NULL) {
                node -> val = max(node -> val, node -> right -> val);
            }
        } else {
            node -> val = node -> right -> val;
        }
    }
}

Node* buildTree(vector<int>& data) {
    Node* root = new Node;
    for(int i=0; i<data.size(); ++i) {
        updateTree(root, 0, data.size()-1, i, data[i]);
    }

    return root;
}

int queryTree(Node* node, int A, int B, const int a, const int b) {
    if(a<=A && B<=b) {
        return node -> val;
    } else {
        int left, right;
        left = right = 0;
        int M = (A+B)/2;
        if(a<=M) {
            left = queryTree(node -> left, A, M, a, b);
        }
        if(M<b) {
            right = queryTree(node -> right, M+1, B, a, b);
        }
        return max(left, right);
    }
}

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

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

    vector<int> data(N);
    for(int i=0; i<N; ++i) {
        fin >> data[i];
    }

    Node* root = buildTree(data);

    int q, a, b;
    for(int i=0; i<M; ++i) {
        fin >> q >> a >> b;
        if(q == 0) {
            fout << queryTree(root, 0, N-1, a-1, b-1) << '\n';
        } else {
            updateTree(root, 0, N-1, a-1, b);
        }
    }

    return 0;
}