f
i
r
s
t
n
u
m
b
e
r
r
e
a
l
p
a
r
t
1
i
m
a
g
i
n
a
r
y
p
a
r
t
2
s
e
c
o
n
d
n
u
m
b
e
r
r
e
a
l
p
a
r
t
3
i
m
a
g
i
n
a
r
y
p
a
r
t
4
(
1
+
2
i
)
(
3
+
4
i
)
=
-
5
+
1
0
i
1
-
2
2
1
3
-
4
4
3
=
-
5
-
1
0
1
0
-
5