#include <algorithm>
using namespace std;

#define DIM 1<<17

int N, M;
int mx, arb[ DIM<<2 ];

inline int max( const int &a, const int &b ) {

    if( a > b )
        return a;

    return b;
}

inline void query( const int &nod, const int &st, const int &dr, const int &a, const int &b ) {

    int mij;

    if( a <= st && dr <= b ) {

        mx = max( mx, arb[ nod ] );
        return;
    }
    mij = (st+dr) / 2;
    if( a <= mij )
        query( nod<<1, st, mij, a, b );
    if( mij < b )
        query( (nod<<1) + 1, mij+1, dr, a, b );
}

inline void update( const int &nod, const int &st, const int &dr, const int &poz, const int &val ) {

    int mij;

    if( st == dr ) {

        arb[ nod ] = val;
        return;
    }
    mij = (st+dr) / 2;
    if( poz <= mij )
        update( nod<<1, st, mij, poz, val );
    else
        update( (nod<<1) + 1, mij+1, dr, poz, val );
    arb[ nod ] = max( arb[ nod<<1 ], arb[ (nod<<1) + 1 ] );
}

int main() {

    freopen( "arbint.in", "r", stdin );
    freopen( "arbint.out", "w", stdout );

    int i, a, b, poz, tip, val;

    scanf( "%d %d", &N, &M );
    for( i = 1; i <= N; ++i ) {

        scanf( "%d", &val );
        update( 1, 1, N, i, val );
    }
    while( M-- ) {

        scanf( "%d", &tip );
        if( tip == 0 ) {

            scanf( "%d %d", &a, &b );
            mx = 0;
            query( 1, 1, N, a, b );
            printf( "%d\n", mx );
        }
        else {

            scanf( "%d %d", &poz, &val );
            update( 1, 1, N, poz, val );
        }
    }

    return 0;
}