a = ["L","R"]
t = 0
loop{ 
    s = gets.to_i
    if s > 0
        puts "F"
        STDOUT.flush
        if s > 20
            break
        end
    else
        puts a[t]
        STDOUT.flush
        s = gets.to_i
        if s == 0
            puts a[t]
            STDOUT.flush
            s = gets.to_i
            puts a[t]
            STDOUT.flush
            t = 1 - t
        else
            puts "F"
            STDOUT.flush
            if s > 20
                break
            end
        end
    end
    }
loop {
    s = gets
    if s[0] == "M"
        break
    else
        puts "F"
        STDOUT.flush
    end
    }