P4435 [COCI 2017/2018 #2] Garaža
Description
Lately, Slavko’s been studying sequences of natural numbers. He finds a sequence
interesting if the greatest common divisor of all the elements from the sequence is greater
than 1.
Yesterday, he found a sequence consisting of N natural numbers in his garage. Since he
was really bored, he decided to keep himself occupied by asking simple queries. Each query
can be one of the two types:
1. Change the value at position X in the sequence to V.
2. Determine the number of interesting contiguous subarrays contained in the interval
[L, R] of the sequence.
Input Format
The first line of input contains the numbers N and Q (1 ≤ N, Q ≤ $10^5$
), representing the
number of elements in the sequence and the number of queries, respectively.
The following line contains N natural numbers $A_i$
(1 ≤ $A_i$ ≤ $10^9$
) that represent the numbers in
the initial sequence.
Each of the following Q lines contains a query of the following form:
- The first number in the line can be 1 or 2 and represents the type of the query.
- If the query is of type 1, two numbers follow, X (1 ≤ X ≤ N) and V (1 ≤ V ≤ $10^9$
) from
the task.
- If the query is of type 2, two numbers follow, L and R (1 ≤ L ≤ R ≤ N) that represent
the left and right interval boundary.
Output Format
For each query of type 2, output the number of interesting contiguous subarrays from the
task.
Explanation/Hint
**Clarification of the first test case:**
The interval from the $2_{nd}$ to the $5_{th}$ position consists of numbers (4, 3, 9, 1). In it, the following are
interesting contiguous subarrays (denoted with square brackets):
**[4]** 3 9 1, 4 **[3]** 9 1, 4 3 **[9]** 1, 4 **[3 9]** 1