Inverted index: Difference between revisions
Added Kotlin
(Added PowerShell) |
(Added Kotlin) |
||
Line 1,883:
0
$</lang>
=={{header|Kotlin}}==
<lang scala>// version 1.1.51
import java.io.File
val invIndex = mutableMapOf<String, MutableList<Location>>()
val fileNames = mutableListOf<String>()
val splitter = Regex("""\W+""")
class Location(val fileName: String, val wordNum: Int) {
override fun toString() = "{$fileName, word number $wordNum}"
}
fun indexFile(fileName: String) {
if (fileName in fileNames) {
println("'$fileName' already indexed")
return
}
fileNames.add(fileName)
File(fileName).forEachLine { line ->
for ((i, w) in line.toLowerCase().split(splitter).withIndex()) {
var locations = invIndex[w]
if (locations == null) {
locations = mutableListOf<Location>()
invIndex.put(w, locations)
}
locations.add(Location(fileName, i + 1))
}
}
println("'$fileName' has been indexed")
}
fun findWord(word: String) {
val w = word.toLowerCase()
val locations = invIndex[w]
if (locations != null) {
println("\n'$word' found in the following locations:")
println(locations.map { " $it" }.joinToString("\n"))
}
else println("\n'$word' not found")
println()
}
fun main(args: Array<String>) {
// files to be indexed entered as command line arguments
if (args.size == 0) {
println("No file names have been supplied")
return
}
for (arg in args) indexFile(arg)
println()
println("Enter word(s) to be searched for in these files or 'q' to quit")
while (true) {
print(" ? : ")
val word = readLine()!!
if (word.toLowerCase() == "q") return
findWord(word)
}
}</lang>
Contents of files:
<pre>
inv1.txt -> It is what it is.
inv2.txt -> What is it?
inv3.txt -> It is a banana!
</pre>
Sample output:
<pre>$ java -jar inverted_index.jar inv1.txt inv2.txt inv3.txt inv1.txt
'inv1.txt' has been indexed
'inv2.txt' has been indexed
'inv3.txt' has been indexed
'inv1.txt' already indexed
Enter word(s) to be searched for in these files or 'q' to quit
? : cat
'cat' not found
? : is
'is' found in the following locations:
{inv1.txt, word number 2}
{inv1.txt, word number 5}
{inv2.txt, word number 2}
{inv3.txt, word number 2}
? : banana
'banana' found in the following locations:
{inv3.txt, word number 4}
? : it
'it' found in the following locations:
{inv1.txt, word number 1}
{inv1.txt, word number 4}
{inv2.txt, word number 3}
{inv3.txt, word number 1}
? : what
'what' found in the following locations:
{inv1.txt, word number 3}
{inv2.txt, word number 1}
? : a
'a' found in the following locations:
{inv3.txt, word number 3}
? : q
</pre>
=={{header|OCaml}}==
| |||