, if
0
|
|
( )
1,
if
0
x
x
x
f x
x

<
= 
−
≥

10 2
1, if
1
( )
1, if
1
x
x
f x
x
x
+
≥
= 
+
<

11 3
2
3, if
2
( )
1,
if
2
x
x
f x
x
x

−
≤
= 
+
>

12 10
2
1, if
1
( )
,
if
1
x
x
f x
x
x

−
≤
= 
>

13