Added solution to Leetcode problem Task Scheduler

Greedy/(LEETCODE) Task-Scheduler.java

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+/**
+* Solution to Task Scheduler at Leetcode in Java
+* Ref : https://leetcode.com/problems/task-scheduler
+* Problem Statement:
+* Given a characters array tasks, representing the tasks a CPU needs to do, where each letter represents a different task. Tasks could be done in any order. Each task is done in one unit of time. 
+* For each unit of time, the CPU could complete either one task or just be idle.
+* However, there is a non-negative integer n that represents the cooldown period between two same tasks (the same letter in the array), that is that there must be at least n units of time between any two same tasks.
+* Return the least number of units of times that the CPU will take to finish all the given tasks.
+
+Example 1:
+Input: tasks = ["A","A","A","B","B","B"], n = 2
+Output: 8
+Explanation: 
+A -> B -> idle -> A -> B -> idle -> A -> B
+There is at least 2 units of time between any two same tasks.
+**/
+
+public class Solution {
+    public int leastInterval(char[] tasks, int n) {
+        int[] storage = new int[26];
+        for (char c : tasks) {
+            storage[(c - 'A')]++;
+        }
+        int max = 0;
+        int count = 1;
+        for (int num : storage) {
+            if (num == 0) {
+                continue;
+            }
+            if (max < num) {
+                max = num;
+                count = 1;
+            } else if (max == num) {
+                count++;
+            }
+        }
+        int space = (n + 1) * (max - 1) + count;
+        return (space < tasks.length) ? tasks.length : space;
+    }
+}