refactor

README.md

@@ -0,0 +1,21 @@
+```
+// Generates a random.txt file with parameters specified, and exits
+// parameters besides N, are only used internally to specify how big are the chunks written
+<main> -g -N 100000 -b 10 -n 101 -o <filename>
+
+// Sort the input file, using the temporary dir, and the parameters specified, save to the output file
+<main> -i <input-file> -o <output-file> -d <tmp dir> -N 100000 -b 10 -n 101
+
+// If no option is specified, system will prompt for parameters, and use the input data from stdin
+<main>
+```
+
+- option `-i` implies the program is supposed to sort something, and thus is incompatible with `-g`
+- when a parameter is not specified the default values are used:
+  - i = "1.in"
+  - o = "1.out"
+  - d = "tmp"
+  - g isn't set (false)
+  - N = 100000
+  - b = 10
+  - n = 101