vue hello world项目
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/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
const SAFE_LIMIT = 0x80000000;
const SAFE_PART = SAFE_LIMIT - 1;
const COUNT = 4;
const arr = [0, 0, 0, 0, 0];
const primes = [3, 7, 17, 19];
module.exports = (str, range) => {
arr.fill(0);
for (let i = 0; i < str.length; i++) {
const c = str.charCodeAt(i);
for (let j = 0; j < COUNT; j++) {
const p = (j + COUNT - 1) % COUNT;
arr[j] = (arr[j] + c * primes[j] + arr[p]) & SAFE_PART;
}
for (let j = 0; j < COUNT; j++) {
const q = arr[j] % COUNT;
arr[j] = arr[j] ^ (arr[q] >> 1);
}
}
if (range <= SAFE_PART) {
let sum = 0;
for (let j = 0; j < COUNT; j++) {
sum = (sum + arr[j]) % range;
}
return sum;
} else {
let sum1 = 0;
let sum2 = 0;
const rangeExt = Math.floor(range / SAFE_LIMIT);
for (let j = 0; j < COUNT; j += 2) {
sum1 = (sum1 + arr[j]) & SAFE_PART;
}
for (let j = 1; j < COUNT; j += 2) {
sum2 = (sum2 + arr[j]) % rangeExt;
}
return (sum2 * SAFE_LIMIT + sum1) % range;
}
};