diff --git a/.gitignore b/.gitignore
index 7a42fe1..67e8275 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,5 @@ out/
 
 venv
 .venv
+
+.ipynb_checkpoints
\ No newline at end of file
diff --git a/zeta_cpp/completed/2557.cpp b/zeta_cpp/completed/2557.cpp
new file mode 100644
index 0000000..bf5eecb
--- /dev/null
+++ b/zeta_cpp/completed/2557.cpp
@@ -0,0 +1,6 @@
+#include<iostream>
+
+int main() {
+    std::cout<<"Hello World!";
+    return 0;
+}
\ No newline at end of file
diff --git a/zeta_cpp/stdin.txt b/zeta_cpp/stdin.txt
new file mode 100644
index 0000000..e69de29
diff --git a/zeta_python/9375.py b/zeta_python/9375.py
new file mode 100644
index 0000000..39ab2c2
--- /dev/null
+++ b/zeta_python/9375.py
@@ -0,0 +1,13 @@
+TC = int(input())
+
+for _ in range(TC):
+    S = 0
+    T = {}
+    N = int(input())
+    for _ in range(N):
+        p, q = input().split()
+        if q in T:
+            T[q] += 1
+        else:
+            T[q] = 1
+    for i in range()