def read_gen(fname):
    with open(fname, 'rt') as fin:
        for line in fin:
            for val in line.split():
                yield int(val)

def build(a, v, st, dr, pos):
    if st == dr:
        a[pos] = v[st]
    else:
        mid = (st + dr) // 2
        build(a, v, st, mid, pos * 2)
        build(a, v, mid + 1, dr, pos * 2 + 1)
        a[pos] = max(a[pos * 2], a[pos * 2 + 1])

def change(a, nv, pnv, st, dr, pos):
    if st == dr:
        a[pos] = nv
    else:
        mid = (st + dr) // 2
        if pnv <= mid:
            change(a, nv, pnv, st, mid, pos * 2)
        else:
            change(a, nv, pnv, mid + 1, dr, pos * 2 + 1)
        a[pos] = max(a[pos * 2], a[pos * 2 + 1])

def find_max(a, pos, i_left, i_right, c_left, c_right):
    if c_left >= i_left and c_right <= i_right:
        return a[pos]
    else:
        mid = (c_left + c_right) // 2
        s_value = 0
        if i_left <= mid:
            s_value = find_max(a, pos * 2, i_left, i_right, c_left, mid)
        if mid + 1 <= i_right:
            s_value = max(s_value, find_max(a, pos * 2 + 1, i_left, i_right, mid + 1, c_right)) 
        return s_value

if __name__ == "__main__":
    
    it = read_gen("arbint.in")

    n, m = next(it), next(it)
    v = [0] + [next(it) for _ in range(n)]
    a = [0 for _ in range((n + 1) * 4 + 1)]
    """ a[i] = maxmimum if an interval (defined by the subintervals) """
    build(a, v, 1, n, 1)
    with open('arbint.out', 'wt') as fout:
        for _ in range(m):
            t, x, y = next(it), next(it), next(it)
            if t == 0:
                maxv = find_max(a, 1, x, y, 1, n)
                fout.write('{}\n'.format(maxv))
            elif t == 1:
                change(a, y, x, 1, n, 1)