High School Programming League Problems Archive

You are given a sequence of digits, which may be grouped into tuples of four digits each. For each such 4-tuple create two two-digit numbers by taking the first and the third digit as the first number, and the second and the fourth digit as the second number. (See the example below. ) The sum of the resulting numbers is used as the ASCII code of the next letter of a secret password. Write a program for passwords decoding.

Input data specification

The first line contains one positive integer t (1<=t<100) - the number of test cases. For each test case, the first line contains one positive integer n (1<=n<10), while the second line contains 4n digits representing the decrypted password.

Output data specification

For each test case print in a separate line the decrypted password.

Example 1

Input:
2
5
24746211151814964359
1
2244
Output:
GREAT
0

Example explanation: In the first test case we are given five 4-tuples:

2474
6211
1518
1496
4359

and calculate following sums:

27 + 44 = 71
61 + 21 = 82
11 + 58 = 69
19 + 46 = 65
45 + 39 = 84

The results are the ASCII codes of letters G, R, E, A, T respectively.

Scoring

By solving this problem you will score 10 points.