a
b
x1
C
x1
b
c
x1
A
x1
c
a
x1
B
x1
A
C
x1
b
x1
C
B
x1
a
x1
B
A
x1
c
x1
a
a
a
a
a
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A
A
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A
A
A
A
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a
a
a
a
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b
b
b
b
b
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B
B
x1
B
B
B
B
x1
b
b
b
b
x1
c
c
c
c
c
x1
C
C
C
x1
C
C
C
C
x1
c
c
c
c
x1
B
a
a
a
a
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c
A
A
A
x1
A
A
A
b
x1
a
a
a
a
C
x1
C
b
b
b
b
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a
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B
B
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B
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c
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b
b
b
b
A
x1
A
c
c
c
c
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C
C
C
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C
C
C
a
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c
c
c
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B
x1
a
A
x1
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A
a
x1
x1
b
B
x1
x1
B
b
x1
x1
c
C
x1
x1
C
c
x1
x1
2.2
B
A
x1
c
x1
A
A
A
A
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a
a
x1
C
B
x1
a
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B
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c
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b
b
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b
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b
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A
A
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a
a
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A
A
A
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a
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B
B
c
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A
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C
b
b
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C
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a
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c
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c
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a
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a
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A
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C
b
b
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B
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c
c
c
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c
c
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C
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c
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c
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A
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C
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c
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c
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a
a
a
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A
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a
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A
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c
c
c
c
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A
A
b
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B
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b
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c
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A
A
A
b
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C
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C
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a
a
a
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A
A
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c
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A
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C
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C
a
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c
c
c
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B
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A
A
A
b
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a
a
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C
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true
A
A
A
b
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a
a
a
C
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C
C
C
a
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c
c
c
c
B
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B
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b
b
b
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C
C
C
a
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c
c
B
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A
C
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B
a
a
a
a
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A
A
A
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A
c
c
c
c
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C
C
C
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C
C
C
C
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c
c
c
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C
C
C
C
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c
c
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A
c
c
c
c
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C
C
C
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c
c
c
c
c
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C
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b
b
b
b
b
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B
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C
b
b
b
b
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a
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B
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C
C
a
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a
a
a
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A
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B
a
a
a
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A
A
A
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a
a
a
a
a
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A
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C
C
C
C
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c
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A
A
A
b
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B
B
c
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b
A
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B
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b
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c
c
c
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C
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b
b
b
b
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C
C
C
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c
c
c
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C
C
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c
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c
c
c
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C
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A
A
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a
a
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A
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b
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B
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c
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A
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a
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B
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c
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A
c
c
c
c
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A
A
A
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a
a
a
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A
A
A
A
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a
a
a
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c
c
c
c
c
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C
C
C
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C
b
b
b
b
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B
B
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c
a
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B
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b
b
b
b
b
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B
B
B
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B
B
B
c
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b
b
b
A
x1
C
B
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a
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A
A
A
A
x1
a
a
x1
B
A
x1
c
x1
A
A
A
b
x1
a
C
x1
true
a
1
1
566
b
1
1
566
B
1
1
565
c
1
1
566
C
1
1
849
B
1
1
849
C
1
1
565
A
1
1
849
A
1
1
565
c
1
1
0
a
1
1
281
b
1
1
0
C
C
C
a
x1
c
c
c
c
B
x1
A
C
x1
b
x1
C
b
b
b
b
x1
a
B
B
B
x1
A
A
A
A
x1
a
a
a
a
x1
a
b
x1
C
x1
c
a
x1
B
x1
B
B
B
c
x1
b
b
b
b
A
x1
b
B
x1
x1
a
A
x1
x1
A
c
c
c
c
x1
b
C
C
C
x1
B
b
x1
x1
C
B
x1
a
x1
B
B
B
B
x1
b
b
b
b
x1
a
a
a
a
a
x1
A
A
A
x1
A
a
x1
x1
A
A
A
b
x1
a
a
a
a
C
x1
C
C
C
C
x1
c
c
c
c
x1
c
C
x1
x1
C
c
x1
x1
c
c
c
c
c
x1
C
C
C
x1
b
b
b
b
b
x1
B
B
B
x1
B
a
a
a
a
x1
c
A
A
A
x1
B
A
x1
c
x1
b
c
x1
A
x1
NaTT
certifiable-1.6