export namespace Random {
    export function choice<T>(arr: T[], random = Math.random): T {
        let index = arr.length * random()
        return arr[Math.floor(index)]
    }
    export function normal(n = 4) {
        let r = 0
        for (let i = 0; i < n; i++) {
            r += Math.random()
        }
        return r / n
    }
    export function uniform() {
        return Math.random()
    }
}