The D. E. Shaw GroupOA #8
Maximum Size Subarray Sum
估计中等可在线判题
考点(AI 标注)单调栈与堆
For each position i in the array, find the length of the longest contiguous subarray that contains i and has a[i] as its maximum, forming an array b. Output the sum of all elements of b. The subarray may contain other maxima equal to a[i].
The standard input/output, the ranges added by this site, and the examples follow this problem's description.
输入格式
The first line contains n (this site's addition: 1≤n≤100000); the second line contains n integers (this site's addition: −10^9≤a[i]≤10^9). The original snapshot only gives n≤10^5 and no element range; the answer is output as a 64-bit integer.
输出格式
Output the sum of the longest subarray lengths over all positions, stored as a 64-bit integer.
样例 1
输入:
6
10 20 10 9 12 14
输出:
17
样例 2
输入:
2
5 5
输出:
4
样例 3
输入:
3
3 2 1
输出:
6