diff --git a/zeta_python/completed/13305.py b/zeta_python/completed/13305.py
new file mode 100644
index 0000000..8fe5523
--- /dev/null
+++ b/zeta_python/completed/13305.py
@@ -0,0 +1,19 @@
+import sys
+
+
+def solve(N, E, C):
+    S = 0
+
+    m = C[0]
+    for i in range(0, len(E)):
+        if C[i] <= m:
+            m = C[i]
+        S += m * E[i]
+
+    return S
+
+
+if __name__ == '__main__':
+    print(solve(int(sys.stdin.readline()),
+                list(map(int, sys.stdin.readline().split())),
+                list(map(int, sys.stdin.readline().split()))))