Codeforces Round 900 (Div. 3) |
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Finished |
Iva and Pav are a famous Serbian competitive programming couple. In Serbia, they call Pav "papuca" and that's why he will make all of Iva's wishes come true.
Iva gave Pav an array $$$a$$$ of $$$n$$$ elements.
Let's define $$$f(l, r) = a_l \ \& \ a_{l+1} \ \& \dots \& \ a_r$$$ (here $$$\&$$$ denotes the bitwise AND operation).
Note that $$$f(l, r)$$$ is not defined when $$$l>r$$$.
Iva also gave Pav $$$q$$$ queries.
Each query consists of 2 numbers, $$$k$$$ and $$$l$$$, and she wants Pav to find the largest index $$$r$$$ ($$$l \le r \le n$$$), such that $$$f(l, r) \ge k$$$.
Pav wants to solve this problem fast because he doesn't want to upset Iva. He needs your help.
The first line contains a single integer $$$t$$$ ($$$1 \le t \le 10^4$$$) — the number of test cases.
The first line of each test case contains a single integer $$$n$$$ ($$$1 \le n \le 2 \cdot 10^5$$$) — the length of array $$$a$$$.
The second line of each test case contains $$$n$$$ integers $$$a_1, a_2, \dots, a_n$$$ ($$$1 \le a_i \le 10^9$$$) — the elements of array $$$a$$$.
The third line of each test case contains a single integer $$$q$$$ ($$$1 \le q \le 10^5$$$) — the number of queries Iva gave Pav.
The next $$$q$$$ lines of each test case contains two numbers, $$$l$$$ and $$$k$$$ ($$$1 \le l \le n$$$, $$$1 \le k \le 10^9$$$) — the left bound for the subsegment, and the integer $$$k$$$ described in statement.
It is guaranteed that the sum of $$$n$$$ over all test cases does not exceed $$$2 \cdot 10^5$$$. Also, it is guaranteed that the sum of $$$q$$$ over all test cases does not exceed $$$2 \cdot 10^5$$$.
For each query output maximal index $$$r$$$ ($$$l \le r \le n$$$) such that $$$a_l \ \& \ a_{l+1} \ \& \dots \& \ a_r \ \ge \ k$$$.
If such $$$r$$$ doesn't exist, output $$$-1$$$.
3515 14 17 42 3431 72 154 557 5 3 1 741 75 72 32 2719 20 15 12 21 7 1141 154 47 125 7
2 -1 5 1 5 2 2 2 6 -1 5
In the first test case $$$n=5$$$, and the array $$$a = [15, 14, 17, 42, 34]$$$
The first query asks for the biggest index $$$r$$$ such that the $$$f(1, r) \ge 7$$$.
$$$f(1,1) = 15, \ f(1, 2) = 14, \ f(1,3)=0 \ f(1, 4)=0 \ f(1, 5)=0$$$, so $$$r=2$$$ is the answer.
The second query asks for $$$f(2, r) \ge 15$$$. Since such $$$r$$$ doesn't exist, the answer is $$$-1$$$.
The third query asks for $$$f(4, r) \ge 5$$$. $$$f(4, 4) = 42, \ f(4, 5) = 34$$$, so $$$r=5$$$ is the answer.
In the second test case $$$n=5$$$, and the array $$$a= [7, 5, 3, 1, 7]$$$.
For the first query, $$$f(1, r) \ge 7$$$.
$$$f(1, 1)=7, \ f(1, 2)=5, \ f(1, 3) = 1, \ f(1,4) = 1, \ f(1, 5)=1$$$, so the answer to this query is $$$1$$$.
For the second query, $$$f(5, r) \ge 7$$$.
$$$f(5, 5) = 7$$$, so the answer is $$$5$$$.
For the third query, $$$f(2, r) \ge 3$$$.
$$$f(2, 2) = 5, \ f(2, 3) = 1, \ f(2, 4) = 1, \ f(2, 5) = 1$$$, so the answer is $$$2$$$.
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