## Sherlock and Probability

Watson gave a string to Sherlock. It is characters long and consists of only `1`

s and `0`

s. Now he asks: Given an integer , I'll pick two indices and at random between and , both inclusive. What's the probability that both and are `1`

and ?

**Input Format**

First line contains , the number of testcases. Each testcase consists of (the length of ) and in one line and string in second line.

**Output Format**

Print the required probability as an irreducible fraction. If required answer is `0`

, output `0/1`

.

**Constraints**

**Sample input**

```
2
4 3
1011
4 1
1011
```

**Sample output**

```
9/16
5/16
```

**Explanation**

test1: Out of 16 choices, 9 pairs of satisfy our condition.

```
(1,1), (1,3), (1,4), (3,1), (3,3), (3,4), (4,1), (4,3), (4,4)
```

test2: Out of 16 choices, 5 pairs of satisfy our condition.

```
(1,1), (3,3), (4,4), (4,3), (3,4)
```