N, Q = map(int, input().split())
A = [0 if i > 1 else 1 for i in list(map(int, input().split()))]
TXY = [list(map(int, input().split())) for _ in range(Q)]

# N: 処理する区間の長さ
N0 = 2 ** (N).bit_length()
data = [0] * (2 * N0)
# a_k の値を x に更新
def update(k, x):
    k += N0 - 1
    data[k] = x
    while k >= 0:
        k = (k - 1) // 2
        data[k] = data[2 * k + 1] ^ data[2 * k + 2]
# 区間[l, r)のXOR
def query(l, r):
    s = 0
    L = l + N0;
    R = r + N0
    while L < R:
        if R & 1:
            R -= 1
            s ^= data[R - 1]
        if L & 1:
            s ^= data[L - 1]
            L += 1
        L >>= 1;
        R >>= 1
    return s

for i, a in enumerate(A):
    update(i, a)
update(0, 1)

for t, x, y in TXY:
    if t == 1:
        if x == 1:
            continue
        if y == 1:
            update(x - 1, 1)
        else:
            update(x - 1, 0)
    else:
        tmp = query(x - 1, y)
        if tmp == 1:
            print("F")
        else:
            print("S")