largestCommonSubstring

[hhummel]

Strings.longestCommonSubstring gives incorrect results if the first string is shorter than the second one, because it only scans until the length of the first string:

object Strings {
...

def longestCommonSubstring(a: String, b: String) : String = {
def loop(m: Map[(Int, Int), Int], bestIndices: List[Int], i: Int, j: Int) : String = {
if (i > a.length) {
b.substring(bestIndices(1) - m((bestIndices(0),bestIndices(1))), bestIndices(1))
...

Doesn't work:
scala> val lcs = Strings.longestCommonSubstring("the price Is right", "right on!")
lcs: String = ri

Works correctly:
scala> val lcs = Strings.longestCommonSubstring("right on!", "the price is right")
lcs: String = right