Find the largest rectangular area possible in a given histogram where the largest rectangle can be made of a number of contiguous bars. For simplicity, assume that all bars have the same width and the width is 1 unit, there will be N bars height of each bar will be given by the array arr.
Example 1:
Input:
N = 7
arr[] = {6,2,5,4,5,1,6}
Output: 12
Explanation: In this example the largest area would be 12 of height 4 and width 3. We can achieve this
area by choosing 3rd, 4th and 5th bars.
Example 2:
Input:
N = 8
arr[] = {7 2 8 9 1 3 6 5}
Output: 16
Explanation: Maximum size of the histogram
will be 8 and there will be 2 consecutive
histogram. And hence the area of the
histogram will be 8x2 = 16.
Your Task:
The task is to complete the function getMaxArea() which takes the array arr[] and its size N as inputs and finds the largest rectangular area possible and returns the answer.
Expected Time Complxity : O(N)
Expected Auxilliary Space : O(N)
Constraints:
1 ≤ N ≤ 10^{6}
0 ≤ arr[i] ≤ 10^{12}

见题面

见题面