diff --git a/day5/chengfa99.cpp b/day5/chengfa99.cpp
new file mode 100644
index 0000000..7ac80f8
--- /dev/null
+++ b/day5/chengfa99.cpp
@@ -0,0 +1,19 @@
+// 打印九九乘法表
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    for (int i = 1; i < 10; i++)
+    {
+        for (int j = 1; j < 10; j++)
+        {
+            if (j <= i)
+                cout << i << "*" << j << "=" << i * j << "\t";
+        }
+        cout << endl;
+    }
+
+    return 0;
+}
\ No newline at end of file