SDE - 1

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You are given an array 'arr' of length 'n'. Find the index(0-based) of a peak element in the array. If there are multiple peak numbers, return the index of any peak number.

Peak element is defined as that element that is greater than both of its neighbors. If 'arr[i]' is the peak element, 'arr[i - 1]' < 'arr[i]' and 'arr[i + 1]' < 'arr[i]'.

Assume 'arr[-1]' and 'arr[n]' as negative infinity.

Note:

1.  There are no 2 adjacent elements having same value (as mentioned in the constraints).
2.  Do not print anything, just return the index of the peak element (0 - indexed).
3. 'True'/'False' will be printed depending on whether your answer is correct or not.

Example:

Input: 'arr' = [1, 8, 1, 5, 3]

Output: 3

Explanation: There are two possible answers. Both 8 and 5 are peak elements, so the correct answers are their positions, 1 and 3.

Given a rod of length ‘N’ units. The rod can be cut into different sizes and each size has a cost associated with it. Determine the maximum cost obtained by cutting the rod and selling its pieces.

Note:

1. The sizes will range from 1 to ‘N’ and will be integers.

2. The sum of the pieces cut should be equal to ‘N’.

3. Consider 1-based indexing.

Given an array of numbers, find the maximum sum of any contiguous subarray of the array.

For example, given the array [34, -50, 42, 14, -5, 86], the maximum sum would be 137, since we would take elements 42, 14, -5, and 86.

Given the array [-5, -1, -8, -9], the maximum sum would be -1.

Follow up: Do this in O(N) time.

Query on MySQL and basic DBMS.

Basic algorithms used in OS.