add youtube link for 1557

fishercoder1534 · fishercoder1534 · commit d9e1dd016ead · 2020-11-02T07:21:22.000-08:00
diff --git a/README.md b/README.md
@@ -35,7 +35,7 @@ _If you like this project, please leave me a star._ &#9733;
 |1561|[Maximum Number of Coins You Can Get](https://leetcode.com/problems/maximum-number-of-coins-you-can-get/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1561.java) |[:tv:](https://youtu.be/hPe9Z3TiUrA)|Medium|Sort|
 |1560|[Most Visited Sector in a Circular Track](https://leetcode.com/problems/most-visited-sector-in-a-circular-track/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1560.java) ||Easy|Array|
 |1558|[Minimum Numbers of Function Calls to Make Target Array](https://leetcode.com/problems/minimum-numbers-of-function-calls-to-make-target-array/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1558.java) ||Medium|Greedy|
-|1557|[Minimum Number of Vertices to Reach All Nodes](https://leetcode.com/problems/minimum-number-of-vertices-to-reach-all-nodes/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1557.java) ||Medium|Graph|
+|1557|[Minimum Number of Vertices to Reach All Nodes](https://leetcode.com/problems/minimum-number-of-vertices-to-reach-all-nodes/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1557.java) |[:tv:](https://youtu.be/IfsiNU7J-6c)|Medium|Graph|
 |1556|[Thousand Separator](https://leetcode.com/problems/thousand-separator/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1556.java) |[:tv:](https://youtu.be/re2BnNbg598)|Easy|String|
 |1551|[Minimum Operations to Make Array Equal](https://leetcode.com/problems/minimum-operations-to-make-array-equal/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1551.java) | [:tv:](https://youtu.be/A-i2sxmBqAA)|Medium|Math|
 |1550|[Three Consecutive Odds](https://leetcode.com/problems/three-consecutive-odds/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1550.java) | |Easy|Array|
