Add README.txt and commentary

Author: danielsource

README.txt

@@ -0,0 +1,7 @@
+Compile using GNU Make:
+	$ make
+
+And run:
+	$ ./test
+
+Configurable variables are present in config.h

config.h

@@ -16,7 +16,8 @@ static int *init_des(int len) {
 #warning "RAND_MAX is less than or equal to 32767."
 #endif
 static int *init_ran(int len) {
-	int *a = malloc(len * sizeof(int)), c = RAND_MAX/len + 1;
+	int *a = malloc(len * sizeof(int));
+	int c = RAND_MAX/len + 1;	/* https://c-faq.com/lib/randrange.html */
 	for (int i = 0; i < len; ++i)
 		a[i] = rand() / c;
 	return a;
@@ -28,7 +29,7 @@ Metric sort_quick(Sequence seq);
 Metric sort_merge(Sequence seq);
 Metric sort_heap(Sequence seq);
 
-int repeattest = 3;	      /* repeat x times and get the average */
+int repeattest = 3;	/* repeat x times and get the average */
 
 Sequence seqs[] = {
 	{"ascending", init_asc, 2000},

sorts/quick.c

@@ -9,14 +9,14 @@ static void quicksort(int *a, int len) {
 	int i, j, t;
 	for (i = 0, j = len - 1; ; ++i, --j) {
 		if (a[i] < pivot) {
-			do  {
+			do {
 				++i;
 				++M.comp;
 			} while (a[i] < pivot);
 		}
 		++M.comp;
 		if (a[j] > pivot) {
-			do  {
+			do {
 				--j;
 				++M.comp;
 			} while (a[j] > pivot);

test.h

@@ -4,7 +4,7 @@ typedef struct Sequence Sequence;
 
 typedef struct {
 	unsigned long long comp, swap;	/* comparisons, swaps, */
-	double ptime;			/* CPU time (in ms) */
+	double ptime;	/* CPU time (in ms) */
 } Metric;
 
 struct Sequence {