class Bit:

    def __init__(self, N):
        self.size = N
        self.depth = N.bit_length()
        self.tree = [0] * (N + 1)
    
    def add(self, i, x):
        while i < self.size:
            self.tree[i] += x
            i += i & (-i)
    
    def sum0(self, r):
        s = 0
        while r > 0:
            s += self.tree[r]
            r -= r & (-r)
        return s
    
    def get_sum(self, l, r):
        if l <= 1:
            return self.sum0(r)
        else:
            return self.sum0(r) - self.sum0(l - 1)
    
    def lower_bound(self, x):
        s, p = 0, 0
        for i in range(self.depth, -1, -1):
            q = p + (1 << i)
            if q <= self.size and s + self.tree[q] < x:
                s += self.tree[q]
                p += 1 << i
        return p + 1


N, Q = map(int, input().split())
A = list(map(int, input().split()))

bit = Bit(N + 1)
for i in range(N):
    if A[i] > 1:
        bit.add(i + 1, 1)

for i in range(Q):
    t, x, y = map(int, input().split())
    if t == 1:
        if A[x - 1] == 1 and y > 1:
            bit.add(x, 1)
        elif A[x - 1] > 1 and y == 1:
            bit.add(x, -1)
        A[x - 1] = y
    else:
        if x == y:
            print('F')
        else:
            l = bit.lower_bound(bit.sum0(y))
            m = max(l, x)
            if (y - m) % 2 == 0:
                print('F')
            else:
                print('S')