diff --git a/tyro/src/main/java/Code2_SumOfFactorial.java b/tyro/src/main/java/Code2_SumOfFactorial.java
new file mode 100644
index 0000000..f1a7a88
--- /dev/null
+++ b/tyro/src/main/java/Code2_SumOfFactorial.java
@@ -0,0 +1,43 @@
+/**
+ * 给定一个参数N，返回1!+2!+3!+4!+…+N!的结果
+ * 1 + 1*2 + 1*2*3 +....+1*...*N
+ */
+public class Code2_SumOfFactorial {
+    /**
+     * 按照最直接的逻辑计算
+     */
+    public static long factorial(int N){
+        long ret = 1;
+        for(int i =1; i<= N; i++){
+            ret *= i;
+        }
+        return ret;
+    }
+    public static long f1(int N){
+        long ret = 0;
+        for(int i =1; i <= N;i++){
+            ret += factorial(i);
+        }
+        return ret;
+    }
+
+    /**
+     * 优化流程，每次加上一次阶乘的结果
+     * @param N
+     */
+    public static long f2(int N){
+        long last = 1;
+        long ret = 0;
+        for(int i =1; i<= N; i++){
+            last = last*i; // 记录上一次计算的结果
+            ret += last;
+        }
+        return ret;
+    }
+
+    public static void main(String[] arg){
+        int N = 10;
+        System.out.println(f1(N));
+        System.out.println(f2(N));
+    }
+}