#include <fstream>

using namespace std;

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

static constexpr int NMAX = (int)(1e5 + 1);

int n, A[NMAX];

class SegTree
{
    int V[(NMAX << 1)];

private:
    static inline int my_max(int a, int b)
    {
        return ((a > b) ? a : b);
    }

public:
    inline void Initialize(int node, int a, int b)
    {
        if (a == b)
        {
            V[node] = A[a];
            return;
        }

        int mid = ((a + b) >> 1);

        Initialize((node << 1), a, mid);
        Initialize(((node << 1) + 1), (mid + 1), b);

        V[node] = my_max(V[(node << 1)], V[((node << 1) + 1)]);

        return;
    }

    inline void Update(int node, int a, int b, int pos, int val)
    {
        if (a == b)
        {
            V[node] = val;
            return;
        }

        int mid = ((a + b) >> 1);

        if (pos <= mid)
            Update((node << 1), a, mid, pos, val);
        if (pos > mid)
            Update(((node << 1) + 1), (mid + 1), b, pos, val);

        V[node] = my_max(V[(node << 1)], V[((node << 1) + 1)]);

        return;
    }

    inline int Query(int node, int a, int b, int qa, int qb)
    {
        if (qa <= a && b <= qb)
            return V[node];

        int p_left = 0, p_right = 0;

        int mid = ((a + b) >> 1);

        if (qa <= mid)
            p_left = Query((node << 1), a, mid, qa, qb);
        if (qb > mid)
            p_right = Query(((node << 1) + 1), (mid + 1), b, qa, qb);

        return my_max(p_left, p_right);
    }
} T;

int main()
{
    f.tie(nullptr);

    int Q = 0;
    f >> n >> Q;
    for (int i = 1; i <= n; ++i)
        f >> A[i];

    T.Initialize(1, 1, n);

    for (int q = 1; q <= Q; ++q)
    {
        int type = 0, a = 0, b = 0;
        f >> type >> a >> b;

        if (type == 1)
            T.Update(1, 1, n, a, b);
        else
            g << T.Query(1, 1, n, a, b) << '\n';
    }

    return 0;
}