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notes/2_15/insertion_sort.c

+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+void insertion_sort(int *a, int n) {
+	int i, j, t;
+	
+	for (i = 1; i < n; i++) {
+		for (t = a[i], j = i-1; j > -1 && a[j] > t; j--) {
+			a[j+1] = a[j];
+		}
+		a[j+1] = t;
+	}
+}
+
+/**
+ * data - array to sort
+ * n - number of items in the array
+ * s - size of the data items
+ * comparator - pointer to function to compare the data
+ */
+void generic_insertion_sort(void *data, int n, size_t s, int (*compare)(const void *, const void *)) {
+	int i, j;
+	void *t;
+	char *a;
+	
+	// Not allowed to do pointer math, dereference, etc on data
+	// So assign the same address to a pointer we actually can work with
+	a = data;
+	
+	t = malloc(s);
+	
+	for (i = 1; i < n; i++) {
+		  // t = a[i]
+		for (memcpy(t, a + (i*s), s), j = i - 1;
+			 j > -1 && compare(a + (j*s), t) > 0;
+			 j--) {
+			// a[j + 1] = a[j];
+			memcpy(a + ((j+1)*s), a + (j*s), s);
+		}
+		//a[j+1] = t;
+		memcpy(a + ((j+1) * s), t, s);
+	}
+	
+	free(t);
+}
+
+int compare_ints(const void *v1, const void *v2) {
+	return *((const int *) v2) - *((const int *) v1);
+}
+
+int compare_chars(const void *v1, const void *v2) {
+	return *((const char *) v2) - *((const char *) v1);
+}
+
+int compare_strings(const void *v1, const void *v2) {
+	return strcmp(*(const char **) v1, *(const char **) v2);
+}
+
+int main(int argc, char *argv[]) {
+	int a[10] = {10, 93, 8, 7, 6, 25, 43, 3, 2, 1};
+	int i;
+	
+	char c[10] = "HelloCS327";
+	
+	char *s[10] = {
+		"one",
+		"two",
+		"three",
+		"four",
+		"five",
+		"six",
+		"seven",
+		"eight",
+		"nine",
+		"ten"
+	};
+	
+	insertion_sort(a, sizeof (a) / sizeof (a[0]));
+	
+	
+	generic_insertion_sort(a, sizeof (a) / sizeof (a[0]), sizeof (a[0]), compare_ints);
+	
+	for (i = 0; i < 10; i++) {
+		printf("%d\n", a[i]);
+	}
+	
+	generic_insertion_sort(c, sizeof (c) / sizeof (c[0]), sizeof (c[0]), compare_chars);
+	
+	for (i = 0; i < 10; i++) {
+		printf("%c\n", c[i]);
+	}
+	
+	generic_insertion_sort(s, sizeof (s) / sizeof (s[0]), sizeof (s[0]), compare_strings);
+	for (i = 0; i < 10; i++) {
+		printf("%s\n", s[i]);
+	}
+}
\ No newline at end of file

notes/2_18/macros.c

+//#include <stdio.h>
+
+#define MAX_ROOMS 20
+#define min(x, y) (x < y ? x : y)
+
+#define max(x, y) ({ \
+	typeof (x) _x = x; \
+	typeof (y) _y = y; \
+	_x > _y ? _x : _y; \
+})
+
+int main(int argc, char *argv[]) {
+	MAX_ROOMS;
+
+	min(3, 4);
+	min(foo(x), bar(x));
+	max(foo(x), bar(x));
+
+	if (10 > min(foo(x), bar(x))) {
+	}
+
+	return 0;
+}