mod = 998244353


def main():
    import sys
    input = sys.stdin.readline

    class Bit:
        def __init__(self, n):
            self.size = n
            self.tree = [0] * (n + 1)

        def sum(self, i):
            s = 0
            while i > 0:
                s += self.tree[i]
                i -= i & -i
            return s

        def add(self, i, x):
            while i <= self.size:
                self.tree[i] += x
                i += i & -i

        def lower_bound(self, w):
            if w <= 0:
                return 0
            x = 0
            k = 1 << (self.size.bit_length() - 1)
            while k:
                if x + k <= self.size and self.tree[x + k] < w:
                    w -= self.tree[x + k]
                    x += k
                k >>= 1
            return x + 1

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

    bit = Bit(N)
    for i, a in enumerate(A):
        if a != 1:
            bit.add(i+1, 1)
    for _ 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:
                k = bit.sum(y)
                j = bit.lower_bound(k)
                if j < x:
                    if (y - x) & 1:
                        print("S")
                    else:
                        print("F")
                else:
                    if (y - j) & 1:
                        print("S")
                    else:
                        print("F")


if __name__ == '__main__':
    main()