Nick Thomas
f1be11fca8
git-subtree-dir: 2020 git-subtree-mainline:ab8f135946git-subtree-split:aaabfa90c9
19 lines
541 B
JavaScript
19 lines
541 B
JavaScript
const fs = require('fs');
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Set.prototype.intersect = function(other) {
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let out = new Set();
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other.forEach((entry) => { this.has(entry) && out.add(entry) });
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return out;
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}
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fs.readFile('input', (err, data) => {
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if (err) throw err;
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let groups = data.toString().split("\n\n").map((group) => {
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let people = group.trim().split("\n").map((person) => new Set(person.trim().split("")));
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return people.reduce((sum,person) => sum.intersect(person));
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});
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console.log( groups.reduce((sum, group) => sum + group.size, 0) );
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});
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