Add files

src/helper/random.ts

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+// src
+// https://stackoverflow.com/questions/521295/seeding-the-random-number-generator-in-javascript
+// Mulberry32
+
+export abstract class Random {
+  private static _seed = Math.random();
+
+  public static set seed(value: number) {
+    Random._seed = value;
+  }
+
+  public static getRandom(): number {
+    let t = (Random._seed += 0x6d2b79f5);
+    t = Math.imul(t ^ (t >>> 15), t | 1);
+    t ^= t + Math.imul(t ^ (t >>> 7), t | 61);
+    return ((t ^ (t >>> 14)) >>> 0) / 4294967296;
+  }
+}