#include <cstdio>
#include <algorithm>

using namespace std;

const int NMAX = 100000;

int arint[4*NMAX+1];

void update(int nod, int st, int dr, int pos, int val)
{
    if(st == dr)arint[nod] = val;
    else
    {
        int mid = (st+dr)/2;
        if(pos<=mid)update(2*nod, st, mid, pos, val);
        else update(2*nod+1, mid+1, dr, pos, val);
        arint[nod] = max(arint[2*nod], arint[2*nod+1]);
    }
}

int Ans;

void query(int nod, int st, int dr, int x, int y)
{
    if(x<=st && dr<=y)
    {
        Ans = max(Ans, arint[nod]);
        return;
    }
    int mid = (st+dr)/2;
    if(x<=mid)query(2*nod, st, mid, x, y);
    if(y>mid)query(2*nod+1, mid+1, dr, x, y);
}

int main()
{
    freopen("arbint.in", "r", stdin);
    freopen("arbint.out", "w", stdout);
    int n, m;
    scanf("%d%d", &n, &m);
    for(int i=0; i<n; i++)
    {
        int x;
        scanf("%d", &x);
        update(1, 1, n, i+1, x);
    }
    for(int i=0; i<m; i++)
    {
        int type, x, y;
        scanf("%d%d%d", &type, &x, &y);
        if(type == 0)
        {
            Ans = -1;
            query(1, 1, n, x, y);
            printf("%d\n", Ans);
        }
        else update(1, 1, n, x, y);
    }
    return 0;
}