Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly
Sign up
Appearance settings

Commit 1526e42

Browse files
Added Simple Hash & Better Hash to Hash Table 🎨
1 parent 42857b1 commit 1526e42

File tree

2 files changed

+94
-0
lines changed

2 files changed

+94
-0
lines changed

‎examples/datastructures/hash-table.js

Lines changed: 47 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,47 @@
1+
class HashTable {
2+
constructor() {
3+
this.table = new Array(137);
4+
}
5+
6+
simpleHash(word) {
7+
let total = 0;
8+
for(let i = 0; i < word.length; i++)
9+
total += word.charCodeAt(i);
10+
return total % this.table.length;
11+
}
12+
13+
betterHash(word) {
14+
let total = 0;
15+
for(let i = 0; i < word.length; i++)
16+
total = 37 * total + word.charCodeAt(i);
17+
return total % this.table.length;
18+
}
19+
20+
put(value,whichHash) {
21+
let pos;
22+
if(whichHash == "simpleHash")
23+
pos = this.simpleHash(value);
24+
if(whichHash == "betterHash")
25+
pos = this.betterHash(value);
26+
this.table[pos] = value;
27+
}
28+
29+
get(value,whichHash) {
30+
let hash;
31+
if(whichHash == "simpleHash")
32+
hash = this.simpleHash(value);
33+
if(whichHash == "betterHash")
34+
hash = this.betterHash(value);
35+
return this.table[hash];
36+
}
37+
38+
showAll() {
39+
let str = "";
40+
for (let i = 0; i < this.table.length; i++)
41+
if(this.table[i] !=undefined)
42+
str += i + " : " + this.table[i] + "\n";
43+
return str;
44+
}
45+
}
46+
47+
module.exports = HashTable;

‎test/datastructures/hash-table.test.js

Lines changed: 47 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,47 @@
1+
const expect = require('chai').expect;
2+
const HashTable = require('../../examples/datastructures/hash-table');
3+
4+
describe('=> HASH TABLE', function() {
5+
let names;
6+
before(function () {
7+
names = new HashTable();
8+
});
9+
10+
it('should create an Empty Hash Table', function(done) {
11+
expect(names.table).to.deep.equal([]);
12+
done();
13+
});
14+
15+
describe('=> simpleHash', function() {
16+
before(function () {
17+
names = new HashTable();
18+
});
19+
20+
it('should put only 1 value of "Clayton" & "Raymond" in Hash Table bcz of Simple Hash', function(done) {
21+
names.put("Clayton","simpleHash");
22+
names.put("Raymond","simpleHash");
23+
expect(names.showAll()).to.equal("45 : Raymond\n");
24+
done();
25+
});
26+
27+
after(function() {
28+
names = new HashTable();
29+
});
30+
});
31+
32+
describe('=> betterHash', function() {
33+
it('should put both values of "Clayton" & "Raymond" in Hash Table bcz of Simple Hash', function(done) {
34+
names.put("Clayton","betterHash");
35+
names.put("Raymond","betterHash");
36+
expect(names.showAll()).to.equal("88 : Clayton\n92 : Raymond\n");
37+
done();
38+
});
39+
});
40+
41+
it('should get value from Hash Table',function() {
42+
names.put("New","betterHash");
43+
expect(names.get("New","betterHash")).to.equal("New");
44+
expect(names.get("xxx","betterHash")).to.equal(undefined);
45+
});
46+
47+
});

0 commit comments

Comments
(0)

AltStyle によって変換されたページ (->オリジナル) /