Not uniformly random, Problem 5.10

[umbs]

In Chapter 5, problem 10, reader is asked to generate a uniformly random number within a range [a,b].

The solution provided is not uniformly random. My method to test is given here:

https://gist.github.com/umbs/5b1557b585d2ed068d7169554db1e62d

Results after multiple runs within various ranges are:

[1]
$ ./a.exe 1 10
1 = 0.000700
2 = 0.008300
3 = 0.046000
4 = 0.114200
5 = 0.206200
6 = 0.252600
7 = 0.199500
8 = 0.115600
9 = 0.045000
10 = 0.011400

==========

$ ./a.exe 10 15
10 = 0.015200
11 = 0.098200
12 = 0.235200
13 = 0.306700
14 = 0.238000
15 = 0.090900

===========

$ ./a.exe 101 120
101 = 0.000000
102 = 0.000000
103 = 0.000400
104 = 0.001300
105 = 0.005100
106 = 0.014100
107 = 0.038200
108 = 0.076600
109 = 0.115500
110 = 0.159100
111 = 0.173200
112 = 0.163000
113 = 0.119800
114 = 0.074000
115 = 0.037500
116 = 0.015400
117 = 0.005200
118 = 0.001400
119 = 0.000100
120 = 0.000100