BiggestDuplicate | Topcoder Archive

Problem Statement

You are given a int[] containing a list of non-negative integers. Find and return the largest one that is duplicated in the list. If there are no duplicates, return -1.

Definition

Class:: BiggestDuplicate
Method:: findLargest
Parameters:: int[]
Returns:: int
Method signature:: int findLargest(int[] x)
(be sure your method is public)

Constraints

x will contain between 2 and 50 elements, inclusive.
Each element of x will be between 0 and 1000, inclusive.

Examples

```
{ 0, 1, 20, 18, 20, 18, 3 }
```
```
Returns: 20
```
The values 18 and 20 are both duplicated, and 20 is the largest of these.
```
{ 15, 12, 3, 15, 7, 12, 15, 7, 12 }
```
```
Returns: 15
```
Notice that 15 and 12 each appear many times. Anything appearing more than once is a duplicate.
```
{ 1, 2, 3, 4, 5 }
```
```
Returns: -1
```
There are no duplicates here.
```
{ 5, 8, 5, 2 }
```
```
Returns: 5
```
Notice that 5, while not the largest element, is the only one that is duplicated.

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