Improved tasks 55, 72, 295

Author: javadev

src/main/scala/g0001_0100/s0055_jump_game/readme.md

@@ -35,7 +35,7 @@ Return `true` _if you can reach the last index, or_ `false` _otherwise_.
 ```scala
 object Solution {
     def canJump(nums: Array[Int]): Boolean = {
-        var sz = nums.length
+        val sz = nums.length
         // We set tmp to 1 so it won't break on the first iteration
         var tmp = 1
 

src/main/scala/g0001_0100/s0072_edit_distance/readme.md

@@ -46,7 +46,7 @@ object Solution {
             return minDistance(w2, w1)
         }
 
-        var dp = Array.range(0, n2 + 1)
+        val dp = Array.range(0, n2 + 1)
 
         for (j <- 0 to n2) {
             dp(j) = j

src/main/scala/g0201_0300/s0295_find_median_from_data_stream/readme.md

@@ -54,7 +54,7 @@ class MedianFinder() {
     private val maxHeap = mutable.PriorityQueue.empty[Int]
     private val minHeap = mutable.PriorityQueue.empty[Int](Ordering.Int.reverse)
 
-    def addNum(num: Int) {
+    def addNum(num: Int): Unit = {
         maxHeap += num
         minHeap += maxHeap.dequeue()
 
@@ -68,7 +68,6 @@ class MedianFinder() {
         else
             (maxHeap.head + minHeap.head).toDouble / 2
     }
-
 }
 
 /*