Array Query Tasks
Xem dạng PDFYou are given an integer array ~A~ with ~N~ elements.
There are ~T~ independent instructions.
Each instruction asks for a specific operation on the array, and the result must be printed immediately.
Your task is to process all instructions efficiently.
Input
Line 1: Two integers ~N~ and ~T~
- ~N~: number of elements in the array
- ~T~: number of instructions
- ~1 ≤ N, T ≤ 2·10^{5}~
Line 2: ~N~ integers
~A_0, A_1, ..., A_{N-1}~ ~(0 ≤ A_i ≤ 10^{5})~Next ~T~ lines: each line contains one instruction in one of the following forms:
sumsub i j
→ Sum of elements from ~A_i~ to ~A_j~ (inclusive)maxleft i
→ Maximum value in ~A_0~ to ~A_{i-1}~
→ If ~i = 0~, output-1minright i
→ Minimum value in ~A_{i+1}~ to ~A_{N-1}~
→ If ~i = N-1~, output-1sumof k
→ Two values whose sum equals ~k~
→ If none exists, output-1 -1maxk l
→ Maximum subarray sum with length exactly ~l~
→ If ~l > N~, output-1mink l
→ Minimum subarray sum with length exactly ~l~
→ If ~l > N~, output-1countk k
→ Number of subarrays with sum equal to ~k~
→ If none exists, output-1
Output
Print ~T~ lines.
Each line contains the answer for the corresponding instruction.
📌 Example
Input
7 4
5 1 3 2 4 6 1
sumsub 1 4
maxleft 3
sumof 7
maxk 3
Output
10
5
3 4
11
💡 Explanation
Each instruction corresponds to a classic array operation.
Efficient algorithms are required due to the large constraints.
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