#include <cstdio>

using namespace std;

int Arb[400100];
int val,start,finish,maxim,pos;
int n,m,x,a,b;

int Maxim(int a, int b)
{
    if(a>b)
        return a;
    return b;
}

void update(int nod, int left, int right)
{
    int div;
    if(left==right)
    {
        Arb[nod]=val;
        return;
    }
    div=(left+right)/2;
    if(pos <= div)
        update(2*nod, left, div);
    else
        update(2*nod+1,div+1,right);
    Arb[nod]=Maxim(Arb[2*nod],Arb[2*nod+1]);
}

void query(int nod, int left, int right)
{
    int div;
    if(start<=left&&right<=finish)
    {
        if(maxim<Arb[nod])
            maxim=Arb[nod];
        return;
    }
    div=(left+right)/2;
    if(start<=div)
        query(2*nod, left, div);
    if(div<finish)
        query(2*nod+1,div+1,right);
}

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