#include <fstream>

#define in "arbint.in"
#define out "arbint.out"
#define Max_Size 100003

std :: ifstream f(in);
std :: ofstream g(out);

int N, M, maxim;
int A[Max_Size], Arb[Max_Size * 3];

void Build_Tree(int node, int st, int dr)
{
    if(st == dr)    Arb[node] = A[st];
    else
    {
        int mij = (st + dr) >> 1;

        Build_Tree(2 * node, st, mij);
        Build_Tree(2 * node + 1, mij + 1, dr);

        Arb[node] = std :: max(Arb[2 * node], Arb[2 * node + 1]);
    }
}

void Search(int node, int st, int dr, int x, int y)
{
    if(x <= st && dr <= y)
    {
        maxim = std :: max(maxim, Arb[node]);
        return;
    }
    else
    {
        int mij = (st + dr) >> 1;

        if(x <= mij)    Search(2 * node, st, mij, x, y);
        if(y > mij)     Search(2 * node + 1, mij + 1, dr, x, y);
    }
}

void Update(int node, int st, int dr, int poz, int el)
{
    if(st == dr)    Arb[node] = el;
    else
    {
        int mij = (st + dr) >> 1;

        if(poz <= mij)  Update(2 * node, st, mij, poz, el);
        else
        if(poz > mij)   Update(2 * node + 1, mij + 1, dr, poz, el);

        Arb[node] = std :: max(Arb[2 * node], Arb[2 * node + 1]);
    }
}

int main()
{
    f >> N >> M;

    for(int i = 1; i <= N; ++i) f >> A[i];

    Build_Tree(1, 1, N);

    for(int tip, x, y, i = 1; i <= M; ++i)
    {
        f >> tip >> x >> y;

        if(!tip)
        {
            maxim = -1;
            Search(1, 1, N, x, y);

            g << maxim << '\n';
        }
        else    Update(1, 1, N, x, y);
    }

    g.close();
    return 0;
}