#include <iostream>
#include <cstdio>
using namespace std;
const int MAXN = 100000;

int segTree[2*MAXN+1], N, M;

void update(int nod, int left, int right, int poz, int value)
{
    if( left == right )
        segTree[ nod ] = value;
    else
    {
        int m = (left + right)/2;

        if( poz <= m && 2*nod <= 2*N - 1 )
            update( 2*nod, left, m, poz, value );
        if( poz > m && 2*nod + 1 <= 2*N - 1 )
            update( 2*nod + 1, m + 1, right, poz, value );
    }

    int maxLeft = -1, maxRight = -1;
    if( 2*nod <= 2*N - 1 )
        maxLeft = segTree[ 2*nod ];

    if( 2*nod + 1 <= 2*N - 1 )
        maxRight = segTree[ 2*nod + 1 ];

    if( maxLeft != -1 || maxRight != -1 )
        segTree[ nod ] = max( maxLeft, maxRight );
}

//max dintre a si b
int maxim = -1;

void querry(int nod, int left, int right, int a, int b)
{
    if( a <= left && right <= b )
        maxim = max( maxim, segTree[ nod ] );
    else
    {
        int m = (left + right)/2;

        if( a <= m && 2*nod <= 2*N - 1 )
            querry( 2*nod, left, m, a, b );
        if( m < b && 2*nod + 1 <= 2*N - 1 )
            querry( 2*nod + 1, m + 1, right, a, b);
    }
}

void citire()
{
    scanf("%d %d",&N, &M);
    for(int i = 1; i <= N; i++)
    {
        int x; scanf("%d",&x);
        update(1,1,N,i,x);
    }
}

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

    citire();

    for(int i = 1; i <= M; i++)
    {
        int cod, a, b; scanf("%d %d %d",&cod,&a,&b);

        if( cod == 0 )
        {
            maxim = -1;
            querry(1, 1, N, a, b);
            printf("%d\n",maxim);
        }
        else update(1, 1, N, a, b);
    }

    return 0;
}