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new file mode 100644
index 0000000..cf024ee
--- /dev/null
+++ b/samples/16square
@@ -0,0 +1,79 @@
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diff --git a/samples/9square b/samples/9square
new file mode 100644
index 0000000..cd51566
--- /dev/null
+++ b/samples/9square
@@ -0,0 +1,44 @@
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diff --git a/samples/error1 b/samples/error1
new file mode 100644
index 0000000..bab3638
--- /dev/null
+++ b/samples/error1
@@ -0,0 +1,8 @@
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diff --git a/samples/error2 b/samples/error2
new file mode 100644
index 0000000..86ee25b
--- /dev/null
+++ b/samples/error2
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