# ZCC Loves Intersection

Time Limit: 2000/1000 MS (Java/Others)

Memory Limit: 131072/131072 K (Java/Others)

## Description

After beats all opponents in 3-dimension-world OI, ZCC feels bored and sets about going to other universes. In a universe with D dimension(s), ZCC finds D segments floating in the air. To be more precise: if we build a rectangular coordinate system with D axis, each of the segments is parallel with one axis, whose endpoints have a coordination of which all components belong to the set {x∈Z|0≤x＜N}. For each axis, there is exactly one segment parallel with it.
Each of the D segments changes location every second. Read the pseudo code below for more details:

Every second, from every pair of segments intersect, ZCC acquires a unit of Energy. Calculate the Expectation of the amount of the acquired energy per second please.

## Input

There are several test cases in one input file. EOF indicates the end of input file.
Every test case contain two positive numbers N, D in one line.
It is guaranteed that 1＜N≤10^9, D≤99. The number of test cases≤10.

## Output

For each test case, output a line with an integer or an irreducible fraction p/q, which is the Expectation.

## Sample Input

2 2
3 3
5 5

## Sample Output

1
49/81
18/625

HintFor the first test case of the sample input, there are 2 segments in a 2*2 lattice.
Because two endpoint couldn’t coincide, two segments must be (0,y)-(1,y) and (x,0)-(x,1). (x, y∈{0,1})
Thus, they always intersect at (x,y). As an irreducible fraction the answer is 1/1, where q = 1, so we should output an integer 1 instead. 

## Source

2014 Multi-University Training Contest 2