Remove "framework"

src/helper/random.ts

@@ -0,0 +1,20 @@
+import { polyfillImul } from './polyfill-imul';
+
+export class Random {
+  public constructor(private seed: number) {
+    polyfillImul();
+  }
+
+  public get next(): number {
+    // result is in [0, 1)
+    return ((2 ** 31 - 1) & (this.seed = Math.imul(48271, this.seed))) / 2 ** 31;
+  }
+
+  public choose<T>(list: Array<T>): T {
+    return list[Math.floor(this.randomInInterval(0, list.length))];
+  }
+
+  public randomInInterval(aClosed: number, bOpen: number): number {
+    return (bOpen - aClosed) * this.next + aClosed;
+  }
+}