#include <fstream>
#include <stdio.h>
using namespace std;

#define dim 100001


int n,m;
int Arb[4*dim];

void Update(int node, int left, int right, int index, int val)
{
    if(left==right)
    {
        Arb[node]=val;
        return;
    }

    int mij=(left+right)/2;
    if(index<=mij) Update(2*node,left,mij,index,val);
    else Update(2*node + 1,mij+1,right,index,val);

    Arb[node]=Arb[2*node]>Arb[2*node + 1]?Arb[2*node]:Arb[2*node + 1];
}

void Query(int node,int left,int right,int a,int b,int &maxim)
{
    if(a<=left && right <= b)
    {
        if(maxim<Arb[node])maxim=Arb[node];
        return ;
    }
    int mij=(left+right)/2;
    if(a<=mij) Query(2*node,left,mij,a,b,maxim);
    if(mij<b) Query(2*node+1,mij+1,right,a,b,maxim);
}

int main()
{
    FILE *f,*g;
    f=fopen("arbint.in","r");
    g=fopen("arbint.out","w");
    fscanf(f,"%d%d",&n,&m);
    int x,a,b,maxim;
    for(int i=1;i<=n;i++)
    {
        fscanf(f,"%d",&x);
        Update(1,1,n,i,x);
    }
    for(int i=1;i<=m;i++)
    {
        fscanf(f,"%d%d%d",&x,&a,&b);
        if(x==0)
        {
            maxim=-1;
            Query(1,1,n,a,b,maxim);
            fprintf(g,"%d\n",maxim);
        }
        else
        {
            Update(1,1,n,a,b);
        }
    }
    fclose(f);
    fclose(g);
    return 0;
}