44 lines
1.3 KiB
Kotlin
44 lines
1.3 KiB
Kotlin
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class Test20 {
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class Solution {
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fun isValid(s: String): Boolean {
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val stack = ArrayDeque(listOf<Char>())
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for (c in s) {
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when(c){
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')' ->{
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if (stack.isEmpty() || stack.last() != '('){
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return false
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}else{
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stack.removeLast()
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}
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}
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'}' ->{
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if (stack.isEmpty() || stack.last() != '{'){
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return false
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}else{
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stack.removeLast()
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}
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}
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']' ->{
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if (stack.isEmpty() || stack.last() != '['){
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return false
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}else{
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stack.removeLast()
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}
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}
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else -> {
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stack.addLast(c)
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}
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}
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}
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return stack.isEmpty()
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}
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}
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fun test(): Unit {
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println(Solution().isValid("()"))
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println(Solution().isValid("()[]{}"))
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println(Solution().isValid("(]"))
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println(Solution().isValid("]"))
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}
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}
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