#include <fstream>

using namespace std;
ifstream f("arbint.in");
ofstream g("arbint.out");

int n,m,i,x[500005],poz,uj,k,maxi,a,b,muvelet;
int maximum(int a,int b)
{
    if(a>b)return a;
        else return b;
}
int update(int csp, int left, int right)
{
    if(left==right)
    {
        x[csp]=uj;
        return 0;
    }
   int k=(left+right)/2;
    if(poz<=k)update(2*csp,left,k);
            else update(2*csp+1,k+1,right);
    x[csp] = maximum(x[2*csp],x[2*csp+1]);
}
int query(int csp,int left,int right)
{
    if(a<=left && right<=b)
    {
        if(maxi<x[csp])maxi=x[csp];
        return 0;
    }
   int k=(left+right)/2;
    if(a<=k)query(2*csp, left, k);
    if(k<b)query(2*csp+1, k+1, right);
}
int main()
{
    f>>n>>m;
    for (i=1;i<=n;i++)
    {
        f>>uj;
        poz=i;
        update(1,1,n);
    }
    for (i=1;i<=m;i++)
    {
        f>>muvelet>>a>>b;
        if(muvelet==1)
        {
            poz=a;
            uj=b;
            update(1,1,n);
        }
        else
        {
            maxi=-1;
            query(1,1,n);
            g<<maxi<<"\n";
        }
    }
}