Add solution for "Apply Operations To An Array" problem

khemssharma · khemssharma · commit be321f3cbcdf · 2025-03-01T12:01:03.000+05:30
diff --git a/JavaScript/leetcode 2046 b/JavaScript/leetcode 2046
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+# 2460. Apply Operations To An Array
+`Array` `Two Pointers` `Simulation`
+
+You are given a 0-indexed array nums of size n consisting of non-negative integers.
+
+You need to apply n - 1 operations to this array where, in the ith operation (0-indexed), you will apply the following on the ith element of nums:
+
+If nums[i] == nums[i + 1], then multiply nums[i] by 2 and set nums[i + 1] to 0. Otherwise, you skip this operation.
+After performing all the operations, shift all the 0's to the end of the array.
+
+For example, the array [1,0,2,0,0,1] after shifting all its 0's to the end, is [1,2,1,0,0,0].
+Return the resulting array.
+
+Note that the operations are applied sequentially, not all at once.
+
+ 
+
+**Example 1**:
+
+> **Input**: nums = [1,2,2,1,1,0]
+    **Output**: [1,4,2,0,0,0]
+    **Explanation**: We do the following operations:
+    - i = 0: nums[0] and nums[1] are not equal, so we skip this operation.
+    - i = 1: nums[1] and nums[2] are equal, we multiply nums[1] by 2 and change nums[2] to 0. The array becomes [1,4,0,1,1,0].
+    - i = 2: nums[2] and nums[3] are not equal, so we skip this operation.
+    - i = 3: nums[3] and nums[4] are equal, we multiply nums[3] by 2 and change nums[4] to 0. The array becomes [1,4,0,2,0,0].
+    - i = 4: nums[4] and nums[5] are equal, we multiply nums[4] by 2 and change nums[5] to 0. The array becomes [1,4,0,2,0,0].
+    After that, we shift the 0's to the end, which gives the array [1,4,2,0,0,0].
+
+**Example 2**:
+
+> **Input**: nums = [0,1]
+    **Output**: [1,0]
+    **Explanation**: No operation can be applied, we just shift the 0 to the end.
+ 
+
+# Solution 
+```javascript []
+var applyOperations = function (nums) {
+    for (let i = 0; i < nums.length - 1; i++) {
+        if (nums[i] === nums[i + 1]) {
+            nums[i] *= 2;
+            nums[i + 1] = 0;
+        }
+    }
+    let i = 0;
+    for (let j = 0; j < nums.length; j++) { // grows window
+        if (nums[j] !== 0) {
+            [nums[i], nums[j]] = [nums[j], nums[i]]
+            i++; // shrinks the window of zeroes
+        } 
+    }
+    return nums;
+};
+```
