You are given two alphanumeric ASCII strings. An ancient manuscript says those strings contain a hidden password. Decode it!

The first string may be grouped into tuples of six characters each. For each such 6-tuple, taking from the i-th character (start counting from 0) the i-th bit of its ASCII code gives you a number (call it a), and likewise taking the (i+3 mod 6)-th bits gives you another number (call it b).

These two numbers tell you about the next two characters to be included in the password, namely the a-th and the b-th character from the second string (count starting from 0 as usual).

### Input

First, you are given t (t<100) - the number of test cases.

Each of the test cases starts with one number n (n < 100) - the number of 6-tuples in the first string, followed by the two strings in separate lines (please have a look at the example to see the correct format). The second string is 64 characters long.

Successive test cases are separated by an empty line.

### Output

For each of the test cases, output its hidden password in a separate line.

### Example

```Input:
2
2
qwe345 rf3Arg
XSBSRasdew9873465hkldsfsalndfvnfq489uqovkLKJHaeDaae555Sk5asdpASD

3
2S4J5K 111111 lrtb2A

Output:
keep
coding

Explanation
Let us have a look at the first 6-tuple: qwe345

char. ASCII code
q   113 = 01110001B
w   119 = 01110111B
e   101 = 01100101B
3    51 = 00110011B
4    52 = 00110100B
5    53 = 00110101B

a(blue bits)  = 110111B = 55
b(green bits) = 101110B = 46
```

### Scoring

By solving this problem you score 10 points.

 Added by: kuszi Date: 2012-09-10 Time limit: 1s Source limit: 50000B Memory limit: 1536MB Cluster: Cube (Intel G860) Languages: All except: ASM32-GCC ASM64 GAWK MAWK BC C-CLANG CPP14-CLANG CPP14 COBOL COFFEE D-CLANG D-DMD DART ELIXIR FANTOM FORTH GOSU GRV JS-MONKEY KTLN NIM NODEJS OBJC OBJC-CLANG OCT PICO PROLOG PYPY PYPY3 PY_NBC R RACKET RUST CHICKEN SED SQLITE SWIFT UNLAMBDA VB.NET Resource: High School Programming League 2012