#include <cstdio>
#define filein "arbint.in"
#define fileout "arbint.out"
#define MAX(a,b) (a>b)?(a):(b)
using namespace std;

int aint[500001];
int N,K;

int Answer;

void Update(int nod, int st, int dr, int poz, int val);
void Query(int nod, int st, int dr, int x, int y);

int main()
{
    FILE *in,*out;
    in=fopen(filein,"r");
    out=fopen(fileout,"w");
    fscanf(in,"%d%d",&N,&K);
    register int i;
    int x,y;
    int todo;
    for (i=1; i<=N; i++)
    {
        fscanf(in,"%d",&x);
        Update(1,1,N,i,x);
    }
    for (i=1; i<=K; i++)
    {
        fscanf(in,"%d%d%d",&todo,&x,&y);
        if (todo==0)
        {
            Answer=0;
            Query(1,1,N,x,y);
            fprintf(out,"%d\n",Answer);
        }
        else if (todo==1)
            Update(1,1,N,x,y);
    }
    fclose(in);
    fclose(out);
    return 0;
}

void Update(int nod, int st, int dr, int poz, int val)
{
    int med;
    if (st==dr)
    {
        aint[nod]=val;
        return;
    }
    med=(st+dr)>>1;
    if (poz<=med) Update(2*nod,st,med,poz,val);
    else Update(2*nod+1,med+1,dr,poz,val);
    aint[nod]=MAX(aint[2*nod],aint[2*nod+1]);
}

void Query(int nod, int st, int dr, int x, int y)
{
    int med;
    if (x<=st && y>=dr)
    {
        Answer=MAX(Answer,aint[nod]);
        return;
    }
    med=(st+dr)>>1;
    if (x<=med) Query(2*nod,st,med,x,y);
    if (y>med) Query(2*nod+1,med+1,dr,x,y);
}