function HashTable() {
this.table = new Array(137);//137——官方比较好的设置数组大小的值
this.betterHash = betterHash;
this.showDistro = showDistro;
this.put = put;
//this.get=get;
}
function betterHash(data) {
var cons = 31;//此参数的设置是为了避免碰撞
var total = 0;
for ( var i = 0; i < data.length; ++i) {
total += cons * total + data.charCodeAt(i);
}
total = total % this.table.length;
document.write("Hash value: " + data + " -> " + total + "<br />");//测试是否有相同的散列值
if (total < 0) {
total += this.table.length - 1;
}
return parseInt(total);
}
function put(data) {
var pos = this.betterHash(data);
if (this.table[pos] == undefined) {
this.table[pos] = data;
} else {
while (this.table[pos] != undefined) {
pos++;
}
this.table[pos] = data;
}
}
function showDistro() {
for ( var i = 0; i < this.table.length; ++i) {
if (this.table[i] != undefined) {
document.write(i + ": " + this.table[i]);
document.write("<br />");
}
}
}
var hTable = new HashTable();
var someNames = [ "David", "Jennifer", "Donnie", "Raymond", "Cynthia",
"Mike", "Clayton", "Danny", "Jonathan" ];
for ( var i = 0; i < someNames.length; ++i) {
hTable.put(someNames[i]);
}
hTable.showDistro();