2
1
2
1
2
1
1
2
1
2
1
1
2
1
2
1
2
1
1
2
1
2
1
1
2
1
2
1
2
1
1
2
1
2
1
2
1
1
1
2
1
2
2
2
1
0
2
1
0
2
0
1
2
