import java.util.Stack
 
fun main() {
    val br = System.`in`.bufferedReader()
    val stack = Stack<Char>()
 
    val sb = StringBuilder()
    while (true) {
        val sentence = br.readLine()
        if (sentence == ".") {
            break
        }
 
        var balanced = true
        loop@ for (c in sentence) {
            when (c) {
                '(' -> stack.push(c)
                ')' -> {
                    if (stack.isEmpty() || stack.peek() != '(') {
                        balanced = false
                        break@loop
                    }
                    stack.pop()
                }
                '[' -> stack.push(c)
                ']' -> {
                    if (stack.isEmpty() || stack.peek() != '[') {
                        balanced = false
                        break@loop
                    }
                    stack.pop()
                }
            }
        }
 
        sb.append(if (balanced) "yes" else "no").append("\n")
 
        stack.clear()
    }
 
    println(sb)
}

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So when I die (the [first] I will see in (heaven) is a score list).
[ first in ] ( first out ).
Half Moon tonight (At least it is better than no Moon at all].
A rope may form )( a trail in a maze.
Help( I[m being held prisoner in a fortune cookie factory)].
([ (([( [ ] ) ( ) (( ))] )) ]).
 .
.