#include <cstdio>
#include <cstdlib>
#include <vector>
using namespace std;
class SegmentTree{
    private:
    int n,pos,val,start,finish,sol_query;
    vector<int> arb;
    private :void upp(int i,int l,int r,int  ( * comparator ) ( int i, int j )){
        int mid;
        if (l==r){
            arb[i]=val;
            return;
        }
        mid=(l+r)>>1;
        if (pos<=mid)  upp(i<<1,l,mid,comparator);
        else           upp((i<<1)+1,mid+1,r,comparator);
        arb[i]=comparator(arb[i<<1],arb[(i<<1)+1]);
    }
    public : void update(int poz,int value,int ( * comparator ) ( int i, int j )){
        pos=poz;
        val=value;
        upp(1,1,n,comparator);
    }
    private :void que(int i,int l,int r,void ( * comparator ) ( int &max_val, int value )){
        int mid;
        if (start<=l && r<=finish){
            comparator(sol_query,arb[i]);
            return;
        }
        mid=(l+r)>>1;
        if (start<=mid)que((i<<1),l,mid,comparator);
        if (mid<finish)que((i<<1)+1,mid+1,r,comparator);
    }
    public : int query(int l,int r,void ( * comparator ) ( int &max_val, int value )){
        start=l;
        finish=r;
        sol_query=0;
        que(1,1,n,comparator);
        return sol_query;
    }
    void init(int nn){
        arb.resize(5*nn+1,0);
        n=nn;
    }
};
SegmentTree arb;
void cmp1(int &maxi,int val){
    maxi=max(maxi,val);
}
int cmp2(int i,int j){
    return max(i,j);
}
main(){
    int n,m,i,a,b;
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    scanf("%d%d",&n,&m);
    arb.init(n);
    for (i=1;i<=n;++i){
        scanf("%d",&a);
        arb.update(i,a,cmp2);
    }
    while (m--){
        scanf("%d%d%d",&i,&a,&b);
        if (i==0)
            printf("%d\n",arb.query(a,b,cmp1));
        else
            arb.update(a,b,cmp2);
    }
}