#include <stdio.h>
#define maxn 100100
int arb[2*maxn+10],n,m,i,a,b,val,x,start,finish,pos,maxim;
int max(int a,int b) { if(a>=b) return a; return b; }
void update(int nod,int left,int right)
{
    if(left==right)
    {
        arb[nod]=val;
        return;
    }
    int div=(left+right)/2;
    if(pos<=div) update(2*nod,left,div);//stanga
    else update(2*nod+1,div+1,right);//dreapta
    arb[nod]=max(arb[2*nod],arb[2*nod+1]);
}
void query(int nod,int left,int right)
{
    if(start<=left && right<=finish)
    {
        if(maxim<arb[nod]) maxim=arb[nod];
        return ;
    }
    int 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(i=1; i<=n; i++)
    {
        scanf("%d",&x);
        pos=i; val=x;
        update(1,1,n);
    }
    for(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);
        }
    }
}