README + 624

Author: Cappuccinuo

Array/624. Maximum Distance in Arrays/README.md

@@ -0,0 +1,29 @@
+Time spent : 20 min
+
+GIVEN: a list of integer list
+
+RETURNS: the maximum difference between two integers from two different arrays
+
+
+
+EXAMPLES:
+
+Input: 
+
+```
+[[1,2,3],
+ [4,5],
+ [1,2,3]]
+```
+
+Output: 4
+
+DESIGN STRATEGY: 
+
+Since the arrays are already sorted, we don't need to compare every element of the arrays.
+
+The two points being considered for the distance calculation should not both belong to the same array.
+
+Thus, for arrays a and b currently chosen, we can just find the maximum out of a[n - 1] - b[0] and b[m - 1] - a[0] to find the larger distance.
+
+And we keep a track of the element with minimum value and the one with maximum value found so far.

Array/624. Maximum Distance in Arrays/Solution.java

@@ -0,0 +1,17 @@
+class Solution {
+    public int maxDistance(List<List<Integer>> arrays) {
+        int tailIndex = arrays.get(0).size() - 1;
+        int max = arrays.get(0).get(tailIndex);
+        int min = arrays.get(0).get(0);
+        int res = 0;
+        for (int i = 1; i < arrays.size(); i++) {
+            tailIndex = arrays.get(i).size() - 1;
+            int diff1 = Math.abs(max - arrays.get(i).get(0));
+            int diff2 = Math.abs(arrays.get(i).get(tailIndex) - min);
+            res = Math.max(res, Math.max(diff1, diff2));
+            max = Math.max(max, arrays.get(i).get(tailIndex));
+            min = Math.min(min, arrays.get(i).get(0));
+        }
+        return res;
+    }
+}

README.md

@@ -167,6 +167,7 @@
 | 163  | 326  |          [Power of Three][326]           |   Java   |    Easy    | 2017.11.27  |                   Math                   |             |
 | 164  | 654  |        [Maximum Binary Tree][654]        |   Java   |    Easy    | 2017.11.27  |                   Tree                   |             |
 | 165  | 191  |         [Number of 1 Bits][191]          |   Java   |    Easy    | 2017.11.27  |             Bit manipulation             |             |
+| 166  | 624  |    [Maximum Distance in Arrays][624]     |   Java   |    Easy    | 2017.11.27  |                  Array                   |             |
 
 
 [1]:<https://leetcode.com/problems/two-sum/> "Two Sum"
@@ -338,6 +339,7 @@
 [605]:<https://leetcode.com/problems/can-place-flowers/> "Can Place Flowers"
 [606]:<https://leetcode.com/problems/construct-string-from-binary-tree/> "Construct String from Binary Tree"
 [617]:<https://leetcode.com/problems/merge-two-binary-trees/> "Merge Two Binary Trees"
+[624]:<https://leetcode.com/problems/maximum-distance-in-arrays/> "Maximum Distance in Arrays"
 [628]:<https://leetcode.com/problems/maximum-product-of-three-numbers/> "Maximum Product of Three Numbers"
 [637]:<https://leetcode.com/problems/average-of-levels-in-binary-tree/> "Average of Levels in Binary tree"
 [643]:<https://leetcode.com/problems/maximum-average-subarray-i/> "Maximum Average Subarray I"