#include <cstdio>
#include <algorithm>

using namespace std;

int arb[100010];
int sol;

void arbint_update(int nod,int st,int dr,int poz,int val)
{
    if(st==dr)
    {
        arb[nod]=val;
        return;
    }
    int mid=(st+dr)/2;\
    if(poz<=mid) arbint_update(nod*2,st,mid,poz,val);
    else arbint_update(nod*2+1,mid+1,dr,poz,val);
    arb[nod]=max(arb[nod*2],arb[nod*2+1]);
}

void arbint_query(int nod,int st,int dr,int left,int right)
{
    if(left<=st && dr<=right)
    {
        sol=max(sol,arb[nod]);
        return;
    }
    int mid=(st+dr)/2;
    if(left<=mid) arbint_query(nod*2,st,mid,left,right);
    if(mid<right) arbint_query(nod*2+1,mid+1,dr,left,right);
}


int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    int n,m,p,a,b,x;
    scanf("%d%d",&n,&m);
    for(int i=1;i<=n;i++)
    {
        scanf("%d",&x);
        arbint_update(1,1,n,i,x);
    }
    for(int i=1;i<=m;i++)
    {
        scanf("%d%d%d",&p,&a,&b);
        if(p==0) {sol=0;arbint_query(1,1,n,a,b);printf("%d\n",sol);}
        else arbint_update(1,1,n,a,b);
    }
    return 0;
}