Data commit

Task/Balanced-brackets/Kotlin/balanced-brackets.kotlin

@@ -0,0 +1,32 @@
+import java.util.Random
+
+fun isBalanced(s: String): Boolean {
+    if (s.isEmpty()) return true
+    var countLeft = 0  // number of left brackets so far unmatched
+    for (c in s) {
+        if (c == '[') countLeft++
+        else if (countLeft > 0) countLeft--
+        else return false
+    }
+    return countLeft == 0
+}
+
+fun main(args: Array<String>) {
+    println("Checking examples in task description:")
+    val brackets = arrayOf("", "[]", "][", "[][]", "][][", "[[][]]", "[]][[]")
+    for (b in brackets) {
+        print(if (b != "") b else "(empty)")
+        println("\t  " + if (isBalanced(b)) "OK" else "NOT OK")
+    }
+    println()
+
+    println("Checking 7 random strings of brackets of length 8:")
+    val r = Random()
+    (1..7).forEach {
+        var s = ""
+        for (j in 1..8) {
+            s += if (r.nextInt(2) == 0) '[' else ']'
+        }
+        println("$s  " + if (isBalanced(s)) "OK" else "NOT OK")
+    }
+}