CF1566C.MAX-MEX Cut

传统题 时间 2000 ms 内存 256 MiB 5 尝试 1 已通过 1 标签

MAX-MEX Cut

A binary string is a string that consists of characters 00 and 11. A bi-table is a table that has exactly two rows of equal length, each being a binary string.

Let MEX\operatorname{MEX} of a bi-table be the smallest digit among 00, 11, or 22 that does not occur in the bi-table. For example, MEX\operatorname{MEX} for [00111010]\begin{bmatrix} 0011\\ 1010 \end{bmatrix} is 22, because 00 and 11 occur in the bi-table at least once. MEX\operatorname{MEX} for [111111]\begin{bmatrix} 111\\ 111 \end{bmatrix} is 00, because 00 and 22 do not occur in the bi-table, and 0<20 \lt 2.

You are given a bi-table with nn columns. You should cut it into any number of bi-tables (each consisting of consecutive columns) so that each column is in exactly one bi-table. It is possible to cut the bi-table into a single bi-table — the whole bi-table.

What is the maximal sum of MEX\operatorname{MEX} of all resulting bi-tables can be?

Input

The input consists of multiple test cases. The first line contains a single integer tt (1t1041 \le t \le 10^4) — the number of test cases. Description of the test cases follows.

The first line of the description of each test case contains a single integer nn (1n1051 \le n \le 10^5) — the number of columns in the bi-table.

Each of the next two lines contains a binary string of length nn — the rows of the bi-table.

It's guaranteed that the sum of nn over all test cases does not exceed 10510^5.

Output

For each test case print a single integer — the maximal sum of MEX\operatorname{MEX} of all bi-tables that it is possible to get by cutting the given bi-table optimally.

Note

In the first test case you can cut the bi-table as follows:

  • [01]\begin{bmatrix} 0\\ 1 \end{bmatrix}, its MEX\operatorname{MEX} is 22.
  • [1010]\begin{bmatrix} 10\\ 10 \end{bmatrix}, its MEX\operatorname{MEX} is 22.
  • [11]\begin{bmatrix} 1\\ 1 \end{bmatrix}, its MEX\operatorname{MEX} is 00.
  • [01]\begin{bmatrix} 0\\ 1 \end{bmatrix}, its MEX\operatorname{MEX} is 22.
  • [00]\begin{bmatrix} 0\\ 0 \end{bmatrix}, its MEX\operatorname{MEX} is 11.
  • [00]\begin{bmatrix} 0\\ 0 \end{bmatrix}, its MEX\operatorname{MEX} is 11.

The sum of MEX\operatorname{MEX} is 88.

Samples

4
7
0101000
1101100
5
01100
10101
2
01
01
6
000000
111111
8
8
2
12

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