OneCardDraw | Topcoder Archive

Problem Statement

You have several cards, each with a number written on them, given in int[] cards. You also have a int target, which is the value you are hoping to find.

If you select a card at random, what is the probability that what is written on the card matches the target value?

Definition

Class:: OneCardDraw
Method:: pickChance
Parameters:: int[], int
Returns:: double
Method signature:: double pickChance(int[] cards, int target)
(be sure your method is public)

Constraints

cards will contain between 1 and 50 elements, inclusive.
Each element of cards will be between 1 and 10, inclusive.
target will be between 1 and 10, inclusive.

Examples

```
{ 1, 2, 3 }
```
```
1
```
```
Returns: 0.3333333333333333
```
There's 1 card that matches, out of 3 total, giving a 1/3 probability.
```
{ 1, 1, 2, 3 }
```
```
1
```
```
Returns: 0.5
```
Two cards out of 4 match.
```
{ 1, 2, 3, 4, 5, 6, 7, 8 }
```
```
9
```
```
Returns: 0.0
```
Since no cards match, there's no chance at all.

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