#include <fstream>
using namespace std;
ifstream fin ( "arbint.in" );
ofstream fout ( "arbint.out" );
const int NMAX = 1e5;
int aint[4 * NMAX + 1];
int maxy;
void update ( int nod, int st, int dr, int poz, int val ) {
    if ( st == dr ) {
        aint[nod] = val;
        return;
    }
    int mid = ( st + dr ) / 2;
    if ( poz <= mid )
        update ( 2 * nod, st, mid, poz, val );
    else
        update ( 2 * nod + 1, mid + 1, dr, poz, val );
    aint[nod] = max ( aint[2 * nod], aint[2 * nod + 1] );
}
void query ( int nod, int st, int dr, int start, int stop ) {
    if ( st >= start && dr <= stop ) {
        maxy = max ( maxy, aint[nod] );
        return;
    }
    int mid = ( st + dr ) / 2;
    if ( start <= mid )
        query ( 2 * nod, st, mid, start, stop );
    else
        query ( 2 * nod + 1, mid + 1, dr, start, stop );
}
int main () {
    int n, m, x, tip, a, b;
    fin >> n >> m;
    for ( int i = 1; i <= n; i++ ) {
        fin >> x;
        update ( 1, 1, n, i, x );
    }
    for ( int i = 1; i <= m; i++ ) {
        fin >> tip >> a >> b;
        if ( tip == 0 ) {
            maxy = -1;
            query ( 1, 1, n, a, b );
            fout << maxy << '\n';
        } else
            update( 1, 1, n, a, b);
    }
    
    return 0;
}