51 lines
1.2 KiB
JavaScript
51 lines
1.2 KiB
JavaScript
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// https://www.freecodecamp.org/learn/coding-interview-prep/data-structures/create-a-hash-table
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var called = 0;
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var hash = (string) => {
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called++;
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var hashed = 0;
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for (var i = 0; i < string.length; i++) {
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hashed += string.charCodeAt(i);
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}
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return hashed;
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};
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var HashTable = function () {
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this.collection = {};
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// Only change code below this line
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this.add = (k, v) => {
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const keyHash = hash(k);
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if (this.collection[keyHash] === undefined) {
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this.collection[keyHash] = [[k, v]];
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} else {
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this.collection[keyHash].push([k, v]);
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}
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};
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this.remove = (k) => {
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const keyHash = hash(k);
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if (this.collection[keyHash] === undefined) {
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return;
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}
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this.collection[keyHash] = this.collection[keyHash].filter(
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([key, value]) => key !== k
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);
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if (this.collection[keyHash].length === 0) {
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delete this.collection[keyHash];
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}
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};
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this.lookup = (k) => {
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const keyHash = hash(k);
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if (this.collection[keyHash] === undefined) {
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return null;
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}
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for (let [key, value] of this.collection[keyHash]) {
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if (key === k) {
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return value;
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}
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}
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return null;
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};
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// Only change code above this line
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};
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