diff --git a/666/dog.cpp b/666/dog.cpp
index 88d2aa5..02e7dab 100644
--- a/666/dog.cpp
+++ b/666/dog.cpp
@@ -1,22 +1,15 @@
 #include<iostream>
+#include<numeric>
 using namespace std;
- 
-void myswap(int &i,int &j){
-    int x;
-    x=i;
-    i=j;
-    j=x;
-    }
 
 int main(){
+    int zhang,li;
+    cin>>zhang>>li;
 
-    int a,b,c;
-  
-    cin>>a>>b;
-   
-    myswap(a,b);
+    int a=lcm(zhang,li);
+
+    cout<<"张三和李四下次相遇是："<<a<<" 天以后。"<<endl;
 
-    cout<<a<<" "<<b<<endl;
 
     return 0;
 }