#include<cstdio>
const int nmax=1e5+4;
int arb[4*nmax+66],v[nmax];
int n,m,start,finish;
inline int maxim(int a,int b)
{
if(a>b)
return a;
return b;
}
inline void build(int node,int st,int dr)
{
if(st==dr)
{
arb[node]=v[st];
return;
}
int med=(st+dr)>>1;
build(2*node,st,med);
build(2*node+1,med+1,dr);
arb[node]=maxim(arb[2*node],arb[2*node+1]);
}
inline void update(int node,int st,int dr)
{
if(st==dr)
{
arb[node]=finish;
return;
}
int med=(st+dr)>>1;
if(start<=med)
update(2*node,st,med);
else
update(2*node+1,med+1,dr);
arb[node]=maxim(arb[2*node],arb[2*node+1]);
}
inline int query(int node,int st,int dr)
{
if(start<=st&&dr<=finish)
return arb[node];
if(start>dr||finish<st)
return -1;
int med=(st+dr)>>1;
return maxim(query(2*node,st,med),query(2*node+1,med+1,dr));
}
int main()
{
freopen("arbint.in","r",stdin);
freopen("arbint.out","w",stdout);
int i,j;
FILE *fin, *fout;
fin=fopen("arbint.in","r");
fout=fopen("arbint.out","w");
fscanf(fin,"%d%d",&n,&m);
for(i=1;i<=n;++i)
fscanf(fin,"%d",&v[i]);
build(1,1,n);
int op;
while(m--)
{
fscanf(fin,"%d%d%d",&op,&start,&finish);
if(op)
update(1,1,n);
else
fprintf(fout,"%d\n",query(1,1,n));
}
}