In the name of God;

Testlib has nice random functions, here I want to suggest some other ones. The first and the second random functions are available in testlib, but the rest are not.

1, $$$\text{rnd.next(l, r)}$$$, it will return a random number in range $$$l$$$ to $$$r$$$ with equal probabilities :

2, $$$\text{rnd.wnext(l, r, w)}$$$, it will return a random number in range $$$l$$$ to $$$r$$$ with monotonically increasing/decreasing probabilities :

if $$$w = 0$$$ then it will be equal to $$$\text{rnd.next(l, r)}$$$.

if $$$w > 0$$$ :

if $$$w < 0$$$ :

3, $$$\text{rnd.cnext(l, r, c)}$$$, it will return a random number in range $$$l$$$ to $$$r$$$ :

4, \text{