push hard

Author: bibhuti9

Easy/121. Best Time to Buy and Sell Stock.js

@@ -31,6 +31,8 @@ var maxProfit2 = function (prices) {
     return maxProfit;
 }
 
+// [3,3,5,0,0,3,1,4]
+
 /*Method 2 */
 /*  TIME COMPLEXITY O(N2) */
 
@@ -48,4 +50,4 @@ var maxProfit1 = function (prices) {
     return max;
 
 }
-console.log(maxProfit2([7, 1, 5, 3, 6, 4]));
+console.log(maxProfit2([3, 3, 5, 0, 0, 3, 1, 4]));

Easy/496. Next Greater Element I.js

@@ -0,0 +1,26 @@
+/*  
+    496. Next Greater Element I
+    https://leetcode.com/problems/next-greater-element-i/
+*/
+
+/**
+ * @param {number[]} nums1
+ * @param {number[]} nums2
+ * @return {number[]}
+ */
+var nextGreaterElement = function (nums1, nums2) {
+    let i = 0, j = 0, numToPush;
+    for (i = 0; i < nums1.length; i++) {
+        j = nums2.indexOf(nums1[i]);    // Find the nums1 current value index in nums2 array
+        numToPush = -1;
+        for (j = j + 1; j < nums2.length; j++) {
+            if (nums2[j] > nums1[i]) {
+                numToPush = nums2[j];
+                break;
+            }
+        }
+        nums1[i] = numToPush;
+    }
+    return nums1;
+};
+console.log(nextGreaterElement([4, 1, 2], [1, 3, 4, 2]));

Hard/123. Best Time to Buy and Sell Stock III.java

@@ -0,0 +1,16 @@
+class Solution {
+
+    public int maxProfit(int[] prices) {
+        int fb = Integer.MIN_VALUE, sb = Integer.MIN_VALUE;
+        int fs = 0, ss = 0;
+
+        for (int i = 0; i < prices.length; i++) {
+            fb = Math.max(fb, -prices[i]);
+            fs = Math.max(fs, fb + prices[i]);
+            
+            sb = Math.max(sb, fs - prices[i]);
+            ss = Math.max(ss, sb + prices[i]);
+        }
+        return ss;
+    }
+}

Hard/123. Best Time to Buy and Sell Stock III.js

@@ -0,0 +1,20 @@
+/*  This question is solved but by mathmatically */
+
+/**
+ * @param {number[]} prices
+ * @return {number}
+ */
+var maxProfit = function (prices) {
+    var fb = Number.MIN_VALUE, sb = Number.MIN_VALUE;
+    var fs = 0, ss = 0;
+    for (let i = 0; i < prices.length; i++) {
+        fb = Math.max(fb, -prices[i]);
+        fs = Math.max(fs, parseInt(fb) + parseInt(prices[i]));
+
+        sb = Math.max(sb, parseInt(fs) - parseInt(prices[i]));
+        ss = Math.max(ss, parseInt(sb) + parseInt(prices[i]));
+    }
+    return ss;
+};
+
+console.log(maxProfit([3, 3, 5, 0, 0, 3, 1, 4]));

Hard/84. Largest Rectangle in Histogram.js

@@ -0,0 +1,51 @@
+/* This question is solved but TLE */
+
+/**
+ * @param {number[]} heights
+ * @return {number}
+ */
+function reverse(arr, target) {
+    var count = 0;
+    for (let i = 0; i < arr.length; i++) {
+        if (arr[i] >= target) {
+            count++;
+        } else {
+            return count;
+        }
+    }
+    return count;
+}
+function forward(arr, target) {
+    var count = 1;
+    for (let i = 0; i < arr.length; i++) {
+        if (arr[i] >= target) {
+            count++;
+        } else {
+            return count;
+        }
+    }
+    return count;
+}
+
+var largestRectangleArea = function (heights) {
+    var map = new Map();
+    var max = 0;
+    for (let i = 0; i < heights.length; i++) {
+        var forwardCount = forward(heights.slice(i + 1), heights[i]);
+        var reverseCount = reverse(heights.slice(0, i).reverse(), heights[i]);
+        var totalWidth = (parseInt(forwardCount) + parseInt(reverseCount)) * heights[i];
+        // console.log(`${heights[i]} ${totalWidth}`);
+        if (max < totalWidth) {
+            max = totalWidth;
+        }
+        // console.log(forward(heights.slice(i + 1), heights[i]));
+    }
+    return max;
+
+};
+console.log(largestRectangleArea([2, 1, 5, 6, 2, 3]));
+
+// [2,1,5,6,9,2,3]
+// [2,4]
+// [1]
+// [4,2]

Medium/189. Rotate Array.js

@@ -1,13 +1,18 @@
+/*
+    189. Rotate Array
+    https://leetcode.com/problems/rotate-array/
+*/
+
 /**
  * @param {number[]} nums
  * @param {number} k
  * @return {void} Do not return anything, modify nums in-place instead.
  */
 var rotate = function (nums, k) {
-    var ansArray = [];
+    var ansArray = [];  // Create an array
     for (let i = 0; i < nums.length; i++) {
-        ansArray[((i + k) % nums.length)] = nums[i];
+        ansArray[((i + k) % nums.length)] = nums[i];    // Math Login
     }
-    return nums = ansArray
+    return nums = ansArray;
 };
 console.log(rotate([1, 2, 3, 4, 5, 6, 7], 3));

Medium/503. Next Greater Element II.js

@@ -4,25 +4,21 @@
  */
 
 
-
-function findMax(currentElement, arr) {
-    for (let i = 0; i < arr.length; i++) {
-        if (currentElement < arr[i]) {
-            return arr[i];
-        }
-    }
-    return -1;
-}
 var nextGreaterElements = function (nums) {
-    let ansArr = [];
+    var stack = [];
+    for (let i = nums.length - 1; i > 0; i--) {
+        stack.push(nums[i]);
+    }
     for (let i = 0; i < nums.length; i++) {
-        ansArr.push(findMax(nums[i], nums));
+        while (stack[stack.length - 1] <= nums[i]) {
+            stack.pop();
+        }
+        if (stack.length <= 0) {
+            nums[i] = -1;
+        } else {
+            nums[i] = stack[stack.length - 1];
+        }
     }
-    return ansArr;
+    console.log(nums);
 };
-console.log(nextGreaterElements([1, 5, 3, 6, 8]));
-
-// [1, 2, 3, 5,4, 3]=[1, 2, 3, 4, 3  1, 2, 3, 4, 3]
-// [1, 2, 1] = [1, 2, 1  1, 2, 1]
-// [1, 2, 3, 2, 1] = [1, 2, 3, 2, 1  1, 2, 3, 2, 1]
-// [5,4,3,2,1] = [5,4,3,2,1  5,4,3,2,1]
+nextGreaterElements([1, 2, 1]);

Medium/61. Rotate List.js

@@ -0,0 +1,7 @@
+/* This question is not solved */
+
+function ListNode(val, next) {
+    this.val = (val === undefined ? 0 : val)
+    this.next = (next === undefined ? null : next)
+}
+ListNode(20);

Practice Problems/Next Greater Element (NGE).js

@@ -52,4 +52,4 @@ function NextGreaterElement(arr) {
     }
     console.log(map);
 }
-NextGreaterElement([1, 2, 1]);
+NextGreaterElement([1, 3, 4, 2]);

Practice Problems/stack/insertElementAtBottom.js

@@ -1,15 +1,16 @@
+/* Insert Element At Bottom Of the Stack */
+
 function insertElementAtBotton(stack, count, size, desiredElement) {
 
     if (count === size) {
-        stack.push(desiredElement);
         return;
     }
     var num = stack[stack.length - 1];
+    console.log(stack.join(" "));
     stack.pop();
-    console.log(stack);
     insertElementAtBotton(stack, count + 1, size, desiredElement);
     stack.push(num);
-    console.log(stack);
+    console.log(stack.join(" "));
 }
 
 var stack = [1, 2, 3, 4];