#include<cstdio>
int n,m,op,a,b,c,d,p,q,i,j,vmax,v[100100],x[100100],l[100100],r[100100];
FILE *f,*g;
int maxim(int a,int b){
    if(a>b)
        return a;
    return b;
}
void upd(){
    v[a]=b;
    for(i=1;i*p<=n;i++){
        if( l[i] <= a && r[i] >= a ){
            x[i]=0;
            for(j=l[i];j<=r[i];j++){
                x[i]=maxim(x[i],v[j]);
            }
            break;
        }
    }
}
void query(){
    vmax=0;
    c=2000000000;
    d=0;
    for(i=1;i<=n/p+1;i++){
        if( a <= l[i] && r[i] <= b ){
            vmax=maxim(vmax,x[i]);
            if(l[i]<=c)
                c=l[i];
            d=maxim(d,r[i]);
        }
    }
    if( c == 2000000000 && d == 0 )
        c=d=b;
    for(i=a;i<=c;i++){
        vmax=maxim(vmax,v[i]);
    }
    for(i=d;i<=b;i++){
        vmax=maxim(vmax,v[i]);
    }
}
int main(){
    f=fopen("arbint.in","r");
    g=fopen("arbint.out","w");
    fscanf(f,"%d%d",&n,&m);
    for(i=1;i<=n;i++){
        fscanf(f,"%d",&v[i]);
    }
    for(p=1;p*p<=n;p++);
    p--;
    for(i=1;i*p<=n;i++){
        l[i]=p*(i-1)+1;
        r[i]=p*i;
        for(j=l[i];j<=r[i];j++){
            x[i]=maxim(x[i],v[j]);
        }
    }
    while(m--){
        fscanf(f,"%d%d%d",&op,&a,&b);
        if(op==1){
            upd();
        }
        else{
            query();
            fprintf(g,"%d\n",vmax);
        }
    }




    fclose(f);
    fclose(g);
    return 0;
}