#include <iostream>
#include <cstdio>
using namespace std;
int am[400555];
int i ,val,pos;
int n,m,x,a,b,maxim;
void update(int nod,int left,int right){
    if( left == right ){
        am[ nod ] = val;
        return;}

    int mid = (left + right) >> 1;
    if( pos <= mid ) update( nod*2   , left , mid  );
      else           update( nod*2+1 , mid+1, right);

    am[nod] = max( am[2*nod] , am[2*nod+1] );

}
void query(int nod,int left,int right){
    if( a <= left && right <= b ){
        if( am[nod] > maxim ) maxim = am[nod];
        return ;
    }
    int mid = (left + right) >> 1;
    if( a <= mid ) query( nod*2  , left , mid  );
    if( mid < b  ) query( nod*2+1, mid+1, right);
}


int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    scanf("%d %d",&n,&m);
    for(i=1;i<=n;++i){
        scanf("%d ",&val); pos = i;
        update( 1 , 1 , n );
    }
    for(i=1;i<=m;++i){
        scanf("%d %d %d\n",&x,&a,&b);
        if( x == 0  ){
           maxim = -1;
           query( 1 , 1 , n );
           printf("%d\n",maxim);
        }else{
            pos = a; val = b;
            update(1 , 1 , n);
        }
    }
    return 0;
}