48 lines
968 B
JavaScript
48 lines
968 B
JavaScript
module.exports = class Sets {
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static and(set1, ...rest) {
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const output = new Set();
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for (const v of set1) {
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if (rest.every((set) => set.has(v))) {
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output.add(v);
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}
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}
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return output;
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}
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static or(...sets) {
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const output = new Set();
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for (const set of sets) {
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for (const v of set) {
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output.add(v);
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}
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}
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return output;
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}
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static xor(...sets) {
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if (sets.length !== 2) {
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throw new Error('xor is only meaningful on 2 sets');
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}
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const [l, r] = sets;
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const output = new Set();
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for (const v of l) {
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if (!r.has(v)) {
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output.add(v);
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}
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}
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for (const v of r) {
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if (!l.has(v)) {
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output.add(v);
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}
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}
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return output;
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}
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static counts(...sets) {
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const output = new Map();
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for (const set of sets) {
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for (const v of set) {
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output.set(v, (output.get(v) || 0n) + 1n);
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}
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}
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return output;
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}
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};
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