Merge pull request #13 from tejdeepthumma/patch-1

Update detect cycle directed graph.cpp

Author: s-kachroo

detect cycle directed graph.cpp

@@ -1,4 +1,5 @@
 /* https://sapphireengine.com/@/6tfphj */
+/* https://cses.fi/problemset/task/1678 */
 #include<iostream>
 using namespace std;
 
@@ -64,4 +65,4 @@ int main(){
 	cout<<checkCycle(visited)<<endl;     
 
 	return 0;
-}
+}