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

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

const int maxn = 1e5 + 5;
int V[maxn], Aint[maxn << 2], maxx;

class Scanner {
public:
    inline Scanner& operator >> (int &val) {
        while (!(Buff[pos] >= '0' && Buff[pos] <= '9')) {
            Advance();
        }
        val = 0;
        while (Buff[pos] >= '0' && Buff[pos] <= '9') {
            val = (val << 1) + (val << 3) + (Buff[pos] - '0');
            Advance();
        }
        return *this;
    }
private:
    char Buff[1 << 19];
    int pos = (1 << 19) - 1;
    void Advance() {
        if (++pos == (1 << 19)) {
            pos = 0;
            f.read(Buff, 1 << 19);
        }
    }
} fin;

void Build(int node, int left, int right) {
    if (left == right) {
        Aint[node] = V[left];
        return;
    }
    int mid = left + ((right - left) >> 1);
    Build(node << 1, left, mid);
    Build(node << 1 | 1, mid + 1, right);
    Aint[node] = max(Aint[node << 1], Aint[node << 1 | 1]);
}

void Update(int node, int left, int right, int pos, int val) {
    if (left == right) {
        Aint[node] = val;
        return;
    }
    int mid = left + ((right - left) >> 1);
    if (pos <= mid) {
        Update(node << 1, left, mid, pos, val);
    } else {
        Update(node << 1 | 1, mid + 1, right, pos, val);
    }
    Aint[node] = max(Aint[node << 1], Aint[node << 1 | 1]);
}

void Query(int node, int left, int right, int inc, int sf) {
    if (inc <= left && right <= sf)  {
        maxx = max(maxx, Aint[node]);
        return;
    }
    int mid = left + ((right - left) >> 1);
    if (inc <= mid) {
        Query(node << 1, left,  mid, inc, sf);
    }
    if (sf > mid) {
        Query(node << 1 | 1, mid + 1, right, inc, sf);
    }
}

int main() {
    ios_base :: sync_with_stdio (false);
    int n, m, x, y, op, i;
    fin >> n >> m;
    for (i = 1; i <= n; i++) {
        fin >> V[i];
    }
    Build(1, 1, n);
    for (i = 1; i <= m; i++) {
        fin >> op >> x >> y;
        if (op == 0) {
            maxx = -1;
            Query(1, 1, n, x, y);
            fout << maxx <<  "\n";
        } else {
            Update(1, 1, n, x, y);
        }
    }
    f.close();
    fout.close();
    return 0;
}