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 # random-username-generator
 
-Generates random usernames.
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+Generates random usernames using the Mersenne Twister 19937 engine.
+
+## Format
+
+The generated usernames have the format `<random letters><random numbers>`, with count of numbers and total length being randomly generated within a certain range, which can be adjusted via command line arguments.
+
+## Parameters
+
+The following parameters can be specified:
+
+- `--min-char` : The minimum number of characters (including numbers) (default: 8)
+- `--max-char` : The maximum number of characters (including numbers) (default: 10)
+- `--min-num`  : The minimum number of digits (default: 0)
+- `--max-num`  : The maximum number of digits (default: 4)
+- `--count`    : How many usernames should be generated (default: 1)
+- `--seed`     : String used as seed sequence. If not defined, system time will be used instead.