diff --git a/src/7/23/T637677.cpp b/src/7/23/T637677.cpp
new file mode 100644
index 0000000..07588c6
--- /dev/null
+++ b/src/7/23/T637677.cpp
@@ -0,0 +1,7 @@
+/*
+solution of https://www.luogu.com.cn/problem/T637677
+*/
+
+int main(){
+    
+}
\ No newline at end of file
diff --git a/src/7/23/domino.ans b/src/7/23/domino.ans
new file mode 100644
index 0000000..1758ddd
--- /dev/null
+++ b/src/7/23/domino.ans
@@ -0,0 +1 @@
+32
\ No newline at end of file
diff --git a/src/7/23/domino.in b/src/7/23/domino.in
new file mode 100644
index 0000000..aa89ed4
--- /dev/null
+++ b/src/7/23/domino.in
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