using namespace std;
#include <cstdio>
#include <algorithm>
#include <string>
#include <cmath>
#define N 101001
#define sqr 256
#define bucket(x) ( (x)/sqr)
#define first(x) ((x)*sqr)
                 
int x[N], b[N/sqr];
int n,m;

inline void update(int p, int v)
{
    int bb=bucket(p);
    x[p]=v;
    int i;
    for(i=first(bb); i< first(bb+1);++i)
	b[bb]=max(b[bb], x[i]);
}


inline int query(int l, int r)
{

    int sol=0,i;
    int b1=bucket(l), b2=bucket(r);

    for(i=l;i<first(b1+1) && i<=r; ++i) sol=max(x[i], sol);

    for(i=max(first(b2), l); i<=r; ++i) sol=max(sol, x[i]);
    
    for(i=b1+1; i<b2; ++i) sol=max(b[i], sol);

    return sol;
}


int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    scanf("%d %d\n", &n,&m);
    int i,v;
    for(i=1;i<=n;++i){scanf("%d ", &v);update(i-1,v);}
    

    int t, p, q;
    while(m--)
{
	scanf("%d %d %d\n", &t, &p, &q);
	if(t==0) printf("%d\n", query(p-1, q-1));
	else update(p-1,q);
}

    return 0;
}