Kotlin 1 line
\nfun maximumNumberOfStringPairs(a: Array<String>) = a.groupingBy { it.toSortedSet() }.eachCount().count { it.value > 1 }\n
```\nfun maximumNumberOfStringPairs(a: Array<String>) = a.groupingBy { it.toSortedSet() }.eachCount().count { it.value > 1 }\n```
['Kotlin']