#include <fstream>

using namespace std;

ifstream fin("arbint.in");
ofstream fout("arbint.out");
const int NMax=100000;
int N;
int M;
int A[NMax+5],AINT[4*NMax];
int Max=-1;

void Read(){
    fin >> N >> M;
    for(int i=1;i<=N;i++){
        fin >> A[i];
    }
}

void Update(int i, int Left, int Right, int a, int b){
    if(Left==Right){
        AINT[i]=b;
        return;
    }
    int Mid=(Left+Right)/2;
    if(a <= Mid){
        Update(2*i,Left,Mid,a,b);
    }else{
        Update(2*i+1,Mid+1,Right,a,b);
    }

    AINT[i] = max(AINT[2*i],AINT[2*i+1]);
}

void Build(){
    for(int i=1;i<=N;i++){
        Update(1,1,N,i,A[i]);
    }
}

void Query(int i,int Left,int Right,int a,int b){
    if(a<=Left && Right<=b){
        Max = max(Max,AINT[i]);
        return;
    }

    if(a>Right || b<Left){
        return;
    }

    int Mid=(Left+Right)/2;
    Query(2*i,Left,Mid,a,b);
    Query(2*i+1,Mid+1,Right,a,b);
}

void Solve(){
    while(M--){
        int op,a,b;
        fin >> op >> a >> b;
        if(op==1){
            Update(1,1,N,a,b);
        }else{
            Max=-1;
            Query(1,1,N,a,b);
            fout << Max << '\n';
        }
    }
}

int main()
{
    Read();
    Build();
    Solve();
    return 0;
}