4X X X X X X X X X XX X X X S S P 1 2 12 22 1 2...
4 . 4x x x x x x x x x xx x x x S S P
1
2
1
2
2
2
1
2
1
2
1
2
1
2
2
1 2
2
x x x x x x x x P2
1
1 2
1 2
1 2
x1
3
x2
3
x1
x2
x1
2
x x1
.2
x2
2
x1
x2
x1
x2
2
x x1
.2
.
x1
x2
2
4x x1 2
x1
x2
2
x x1
.2
S2
4P S
2
P
. x1
4
x2
4
x1
2
2
x2
2
2
x1
2
x2
2
x1
2
x2
2
S2
2P S S
.2
4P