31 lines
809 B
JavaScript
31 lines
809 B
JavaScript
const opens = ["(", "[", "{", "<"]
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const closes = [")", "]", "}", ">"]
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const scores1 = { ")": 3, "]": 57, "}": 1197, ">": 25137 }
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const scores2 = { ")": 1, "]": 2, "}": 3, ">": 4 }
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function parse(str) {
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let stack = []
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for (let i = 0; i < str.length; i++) {
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let char = str[i]
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if (opens.includes(char)) {
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stack.push(closes[opens.indexOf(char)])
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} else if (char != stack.pop()) {
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return scores1[char]
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}
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}
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return stack.reverse()
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}
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function day10(input, part2) {
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let results = input.split("\n").map(parse)
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if (!part2) {
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return results.filter((e) => !Array.isArray(e)).sum()
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} else {
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return results.filter((e) => Array.isArray(e)).map((e) => e.reduce((a, b) => a * 5 + scores2[b], 0)).medianNumeric()
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}
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}
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