#include <cstdio>
#include <algorithm>
#define NMAX 100001
using namespace std;

int A[4*NMAX+66];
int n,m,val,poz,start,finish,maxim;

inline void Update(int nod,int left,int right){

    if(left == right){
        A[nod] = val;
        return;
    }
    int mijloc = (left+right)/2;
    if(poz <= mijloc)
        Update(2*nod,left,mijloc);
    else Update(2*nod+1,mijloc+1,right);
    A[nod] = max(A[2*nod],A[2*nod+1]);
}

inline void Maxim(int nod,int left,int right){

    if(start <=left && right <=finish){
        if(A[nod] > maxim) maxim = A[nod];
            return;
    }
    int mijloc = (left+right)/2;
    if(start<=mijloc)
    Maxim(2*nod,left,mijloc);
    if(mijloc < finish)
    Maxim(2*nod+1,mijloc+1,right);
}

inline void solve(){

    int cod,a,b;
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    scanf("%d%d",&n,&m);
    for(register int i=1;i<=n;++i){
        scanf("%d",&a);
        poz = i,val = a;
        Update(1,1,n);
    }
    while(m){

        scanf("%d%d%d",&cod,&a,&b);
        if(!cod){
            maxim=-1;
            finish = b;
            start = a;
            Maxim(1,1,n);
            printf("%d\n",maxim);
        }

        else{
                poz = a;
                val = b;
                Update(1,1,n);
        }
    --m;
    }
}

int main(){

    solve();
return 0;
}