diff --git a/README.md b/README.md
index b16d734..7332381 100644
--- a/README.md
+++ b/README.md
@@ -78,4 +78,16 @@ n=()
 a,b=0,1
 for i in range(n):
 a,b=b,a+b
-print(b)
\ No newline at end of file
+print(b)
+
+fn2,fn1=1,1
+fn=0 #当前月份兔子数
+n=2 #月份n
+uplimit=eval(input("兔子数："))
+while fn<=uplimit:
+fn=fn2+fn1
+n+=1
+fn2=fn1 fn2,fn1=fn1,fn
+fn1=fn
+print('第0月份，兔子数达到{}对'.format(n,fn))
+print(第0月份，兔子数达到{}对超过{}.format(n,fn,uplimit))