6
"ab"
""
"abc"
"cd"
"ab"
""
"abcd"
"foo"
".lean"
"αβ"
2
"α_foo_βcc"
"αβ_foo_cc"
"α_foo_βcc"
4
3
7
5
6
0
0
1
2
1
1
6
0
1
4
(1, 0)
(1, 1)
(1, 2)
(2, 0)
(3, 4)
(3, 7)