#include<cstdio>

using namespace std;

const int nmax=1e5+5;

int arb[nmax*4+66];
int a,b,maxim;

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

inline void modif(int node,int st,int dr)
{
    if(st==dr)
    {
        arb[node]=b;
        return;
    }
    int med=(st+dr)/2;
    if(a<=med)
        modif(2*node,st,med);
    else
        modif(2*node+1,med+1,dr);
    arb[node]=max(arb[2*node],arb[2*node+1]);
}

inline void query(int node,int st,int dr)
{
    if(a<=st&&dr<=b)
    {
        if(maxim<arb[node])
            maxim=arb[node];
        return;
    }
    else
    {
        int med=(st+dr)/2;
        if(a<=med)
            query(2*node,st,med);
        if(b>med)
            query(2*node+1,med+1,dr);
    }
}

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