diff --git a/docs/notes/剑指 Offer 题解 - 10~19.md b/docs/notes/剑指 Offer 题解 - 10~19.md
index f913b5da..e7d1d732 100644
--- a/docs/notes/剑指 Offer 题解 - 10~19.md
+++ b/docs/notes/剑指 Offer 题解 - 10~19.md
@@ -98,11 +98,11 @@ public class Solution {
当 n 为 1 时,只有一种覆盖方法:
-
+
当 n 为 2 时,有两种覆盖方法:
-
+
要覆盖 2\*n 的大矩形,可以先覆盖 2\*1 的矩形,再覆盖 2\*(n-1) 的矩形;或者先覆盖 2\*2 的矩形,再覆盖 2\*(n-2) 的矩形。而覆盖 2\*(n-1) 和 2\*(n-2) 的矩形可以看成子问题。该问题的递推公式如下:
@@ -137,6 +137,18 @@ public int RectCover(int n) {
## 解题思路
+当 n = 1 时,只有一种跳法:
+
+
+
+当 n = 2 时,有两种跳法:
+
+
+
+跳 n 阶台阶,可以先跳 1 阶台阶,再跳 n-1 阶台阶;或者先跳 2 阶台阶,再跳 n-2 阶台阶。而 n-1 和 n-2 阶台阶的跳法可以看成子问题,该问题的递推公式为:
+
+
+
```java
public int JumpFloor(int n) {
if (n <= 2)
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diff --git a/notes/剑指 Offer 题解 - 10~19.md b/notes/剑指 Offer 题解 - 10~19.md
index 741289f7..c1ec071a 100644
--- a/notes/剑指 Offer 题解 - 10~19.md
+++ b/notes/剑指 Offer 题解 - 10~19.md
@@ -98,11 +98,11 @@ public class Solution {
当 n 为 1 时,只有一种覆盖方法:
-
+
当 n 为 2 时,有两种覆盖方法:
-
+
要覆盖 2\*n 的大矩形,可以先覆盖 2\*1 的矩形,再覆盖 2\*(n-1) 的矩形;或者先覆盖 2\*2 的矩形,再覆盖 2\*(n-2) 的矩形。而覆盖 2\*(n-1) 和 2\*(n-2) 的矩形可以看成子问题。该问题的递推公式如下:
@@ -137,6 +137,18 @@ public int RectCover(int n) {
## 解题思路
+当 n = 1 时,只有一种跳法:
+
+
+
+当 n = 2 时,有两种跳法:
+
+
+
+跳 n 阶台阶,可以先跳 1 阶台阶,再跳 n-1 阶台阶;或者先跳 2 阶台阶,再跳 n-2 阶台阶。而 n-1 和 n-2 阶台阶的跳法可以看成子问题,该问题的递推公式为:
+
+
+
```java
public int JumpFloor(int n) {
if (n <= 2)