52 lines
852 B
JavaScript
52 lines
852 B
JavaScript
function last (array) {
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return array[array.length - 1]
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}
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let brackets = {
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/**
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* Parse string to nodes tree
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*/
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parse (str) {
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let current = ['']
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let stack = [current]
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for (let sym of str) {
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if (sym === '(') {
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current = ['']
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last(stack).push(current)
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stack.push(current)
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continue
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}
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if (sym === ')') {
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stack.pop()
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current = last(stack)
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current.push('')
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continue
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}
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current[current.length - 1] += sym
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}
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return stack[0]
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},
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/**
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* Generate output string by nodes tree
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*/
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stringify (ast) {
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let result = ''
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for (let i of ast) {
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if (typeof i === 'object') {
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result += `(${brackets.stringify(i)})`
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continue
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}
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result += i
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}
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return result
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}
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}
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module.exports = brackets
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