#include <cstdio>
#include <algorithm>
#include <climits>

const int NMAX = (1 << 17);

using namespace std;

int v[NMAX+5], a[2*NMAX+5];


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

int query(int nod, int st, int dr, int x, int y) {
    int mid = (st + dr) / 2, SOL = 0;
    if (x <= st && dr <= y)
        return a[nod];
    if (x <= mid)
        SOL = max (SOL, query(nod * 2, st, mid, x, y));
    if (y > mid){
        SOL = max (SOL, query(nod * 2 + 1, mid + 1, dr, x, y));
        SOL = max (SOL, query(nod * 2 + 1, mid + 1, dr, x, y));
    }
    return SOL;
}

void init (int nod, int st, int dr) {
    int mid = (st + dr) / 2;
    if (st == dr) {
        a[nod] = v[st];
        return;
    }
    init (nod * 2, st, mid);
    init (nod * 2 + 1, mid + 1, dr);
    a[nod] = max (a[nod * 2], a[nod * 2 + 1]);
}

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

    int n, m, i, p2, op, a, b;
    scanf ( "%d%d", &n, &m );
    for ( i = 1; i <= n; ++i )
        scanf ( "%d", &v[i] );

    p2 = 1;
    while ( p2 < n )
        p2 *= 2;
    init (1, 1, p2);

    for ( i = 1; i <= m; ++i ) {
        scanf ( "%d%d%d", &op, &a, &b );
        if (op == 1)
            update(1, 1, p2, a, b);
        else
            printf ( "%d\n", query (1, 1, p2, a, b) );
    }

    return 0;
}