#include <iostream>
#include <vector>
#include <cstdio>

using namespace std;
typedef int var;

#define BSIZE 500
#define BCOUNT 5000

var V[100005];
var Buck[BCOUNT];

void update(var ind, var val) {
    V[ind] = val;
    if(Buck[ind/BSIZE] <= val)
        Buck[ind/BSIZE] = val;
    else {
        Buck[ind/BSIZE] = -1;
        for(var i=ind/BSIZE*BSIZE; ind%BSIZE; ind++)
            Buck[ind/BSIZE] = max(Buck[ind/BSIZE], val);
    }
}

var query(var l, var r) {
    var i;
    var rez = -1;
    for(i=l; i<=r && i%BSIZE; i++)
        rez = max(rez, V[i]);

    for(var b=i/BSIZE; i+BSIZE<=r; i+=BSIZE, b++)
        rez = max(rez, Buck[b]);

    for(; i<=r; i++)
        rez = max(rez, V[i]);

    return rez;
}

int main()
{
    freopen("arbint.in", "r", stdin);
    freopen("arbint.out", "w", stdout);

    var m, n;
    cin>>n>>m;
    for(var i=1; i<=n; i++) {
        cin>>V[i];
        Buck[V[i]/BSIZE] = max(Buck[V[i]/BSIZE], V[i]);
    }

    var type, a, b;

    while(m--) {
        cin>>type>>a>>b;
        if(type == 1) update(a, b);
        else cout << query(a, b) << '\n';
    }
}