Added practice problem from recent Contest (#422)

gampu · jakobkogler · commit b98a3a74d1c4 · 2019-04-02T20:34:04.000+02:00
diff --git a/src/graph/bipartite-check.md b/src/graph/bipartite-check.md
@@ -46,3 +46,4 @@ cout << (is_bipartite ? "YES" : "NO") << endl;
 ### Practice problems:
 
 - [SPOJ - BUGLIFE](http://www.spoj.com/problems/BUGLIFE/)
+- [Codeforces - Graph Without Long Directed Paths](https://codeforces.com/contest/1144/problem/F)

Original file line number	Diff line number	Diff line change
`@@ -46,3 +46,4 @@ cout << (is_bipartite ? "YES" : "NO") << endl;`
`46`	`46`	`### Practice problems:`
`47`	`47`
`48`	`48`	`- [SPOJ - BUGLIFE](http://www.spoj.com/problems/BUGLIFE/)`
	`49`	`+- [Codeforces - Graph Without Long Directed Paths](https://codeforces.com/contest/1144/problem/F)`