#include <fstream>

using namespace std;
const int nmax = 1e5;

int v[nmax + 1];
int aint[4 * nmax + 1];

void build ( int node, int st, int dr ) {
    if ( st == dr ) {
        aint[node] = v[st];
        return;
    }
    int mij = ( st + dr ) / 2;
    build ( 2 * node, st, mij );
    build ( 2 * node + 1, mij + 1, dr );
    aint[node] = max ( aint[2 * node], aint[2 * node + 1] );
}

void update ( int node, int st, int dr, int poz, int val ) {
    if ( st == dr ) {
        aint[node] = val;
        return;
    }
    int mij = ( st + dr ) / 2;
    if ( poz <= mij ) update ( 2 * node, st, mij, poz, val );
    else update ( 2 * node + 1, mij + 1, dr, poz, val );
    aint[node] = max ( aint[2 * node], aint[2 * node + 1] );
}

int query ( int node, int st, int dr, int a, int b ) {
    if ( a == st && dr == b )
        return aint[node];
    int mij = ( st + dr ) / 2;
    if ( b <= mij )
        return query ( 2 * node, st, mij, a, b );
    if ( a > mij )
        return query ( 2 * node + 1, mij + 1, dr, a, b );
    return max ( query ( 2 * node, st, mij, a, mij ),
                 query ( 2 * node + 1, mij + 1, dr, mij + 1, b ) );
}

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

int main() {
    int n, q, tip, x, k, a, b;

    fin >> n >> q;
    for ( int i = 1; i <= n; i++ )
        fin >> v[i];

    build ( 1, 1, n );

    /**
    tip 0: query: max ( v[a], ..., v[b] )
    tip 1: update: v[x] = k
    **/
    while ( q-- ) {
        fin >> tip;
        if ( tip == 1 ) {
            fin >> k >> x;
            update ( 1, 1, n, k, x );
        } else {
            fin >> a >> b;
            fout << query ( 1, 1, n, a, b ) << '\n';
        }
    }

    return 0;
}