From e098bc87ac1a53472dd46e23627fd1edd5ab90d0 Mon Sep 17 00:00:00 2001
From: Claudio Maggioni <claudio@maggioni.xyz>
Date: Tue, 5 Nov 2019 15:03:46 +0100
Subject: [PATCH] Added exercise 26 (sort cars)

---
 cars/sort_cars.c       |  92 ++++++++++++++++++++++++++++++
 cars/test_sort_cars.sh | 126 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 218 insertions(+)
 create mode 100644 cars/sort_cars.c
 create mode 100755 cars/test_sort_cars.sh

diff --git a/cars/sort_cars.c b/cars/sort_cars.c
new file mode 100644
index 0000000..46f5181
--- /dev/null
+++ b/cars/sort_cars.c
@@ -0,0 +1,92 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct car {
+	char maker[21];
+	char model[21];
+	unsigned int power;
+	unsigned int price;
+};
+
+enum sort {
+	MODEL,
+	MAKER,
+	PRICE,
+	POWER
+};
+
+enum sort sorting = MAKER;
+int asc = 0;
+
+int asc_desc(int o) {
+	if (asc) {
+		return o;
+	} else {
+		return o * -1;
+	}
+}
+
+int compare_cars(const void* car1, const void* car2) {
+	const struct car* c1 = car1;
+	const struct car* c2 = car2;
+	// printf("%s %s %u %u\n", c1->maker, c1->model, c1->power, c1->price);
+	// printf("%s %s %u %u\n", c2->maker, c2->model, c2->power, c2->price);
+
+	switch (sorting) {
+		case MODEL:
+			return asc_desc(strcmp(c1->model, c2->model));
+		case MAKER:
+			return asc_desc(strcmp(c1->maker, c2->maker));
+		case PRICE:
+			return asc_desc(c1->price - c2->price);
+		case POWER:
+			return asc_desc(c1->power - c2->power);
+	}
+}
+
+int main(int argc, const char** argv) {
+	if (argc == 2) {
+		if      (!strcmp(argv[1], "+model")) { sorting = MODEL; asc = 1; }
+		else if (!strcmp(argv[1], "-model")) { sorting = MODEL; asc = 0; }
+		else if (!strcmp(argv[1], "+maker")) { sorting = MAKER; asc = 1; }
+		else if (!strcmp(argv[1], "-maker")) { sorting = MAKER; asc = 0; }
+		else if (!strcmp(argv[1], "+price")) { sorting = PRICE; asc = 1; }
+		else if (!strcmp(argv[1], "-price")) { sorting = PRICE; asc = 0; }
+		else if (!strcmp(argv[1], "+power")) { sorting = POWER; asc = 1; }
+		else if (!strcmp(argv[1], "-power")) { sorting = POWER; asc = 0; }
+		else { fprintf(stderr, "wrong argument\n"); return 3; }
+	} else if (argc > 2) {
+		fprintf(stderr, "wrong arguments\n");
+		return 3;
+	}
+
+	size_t length = 1024, i = 0;
+	struct car* A = malloc(sizeof(struct car) * length);
+	if (!A) {
+		perror("Cannot allocate cars");
+		return 1;
+	}
+	while(!feof(stdin)) {
+		scanf("%s %s %u %u\n", A[i].maker, A[i].model, &A[i].power, &A[i].price);
+		i++;
+		if (i == length) {
+			length *= 2;
+			struct car* B = realloc(A, sizeof(struct car) * length);
+			if (!B) {
+				perror("Cannot expand cars");
+				free(A);
+				return 2;
+			}
+			A = B;
+		}
+	}
+
+	qsort(A, i, sizeof(struct car), compare_cars);
+
+	for (size_t j = 0; j < i; j++) {
+		printf("%s %s %u %u\n", A[j].maker, A[j].model, A[j].power, A[j].price);
+	}
+
+	free(A);
+}
diff --git a/cars/test_sort_cars.sh b/cars/test_sort_cars.sh
new file mode 100755
index 0000000..b971b17
--- /dev/null
+++ b/cars/test_sort_cars.sh
@@ -0,0 +1,126 @@
+#!/bin/sh
+
+#
+# test 1
+#
+cat > test1.in <<EOF
+fiat bravo 105 30000
+bmw 305i 120 50000
+bmw 305 100 45000
+fiat 500 80 25000
+EOF
+./sort_cars < test1.in > test1.out
+cat > test1.expected <<EOF
+fiat bravo 105 30000
+fiat 500 80 25000
+bmw 305i 120 50000
+bmw 305 100 45000
+EOF
+if diff -q test1.out test1.expected; then
+    rm -f test1.out test1.expected
+else
+    echo "Test 1 FAILED"
+    diff test1.out test1.expected
+    exit 1
+fi
+#
+# test 2
+#
+./sort_cars +model < test1.in > test1.out
+cat > test1.expected <<EOF
+bmw 305 100 45000
+bmw 305i 120 50000
+fiat 500 80 25000
+fiat bravo 105 30000
+EOF
+if diff -q test1.out test1.expected; then
+    rm -f test1.out test1.expected
+else
+    echo "Test 2 FAILED"
+    diff test1.out test1.expected
+    exit 1
+fi
+#
+# test 3
+#
+./sort_cars -power < test1.in > test1.out
+cat > test1.expected <<EOF
+bmw 305i 120 50000
+fiat bravo 105 30000
+bmw 305 100 45000
+fiat 500 80 25000
+EOF
+if diff -q test1.out test1.expected; then
+    rm -f test1.out test1.expected
+else
+    echo "Test 3 FAILED"
+    diff test1.out test1.expected
+    exit 1
+fi
+#
+# test 4
+#
+./sort_cars +power < test1.in > test1.out
+cat > test1.expected <<EOF
+fiat 500 80 25000
+bmw 305 100 45000
+fiat bravo 105 30000
+bmw 305i 120 50000
+EOF
+if diff -q test1.out test1.expected; then
+    rm -f test1.out test1.expected
+else
+    echo "Test 4 FAILED"
+    diff test1.out test1.expected
+    exit 1
+fi
+#
+# test 5
+#
+./sort_cars +price < test1.in > test1.out
+cat > test1.expected <<EOF
+fiat 500 80 25000
+fiat bravo 105 30000
+bmw 305 100 45000
+bmw 305i 120 50000
+EOF
+if diff -q test1.out test1.expected; then
+    rm -f test1.out test1.expected
+else
+    echo "Test 5 FAILED"
+    diff test1.out test1.expected
+    exit 1
+fi
+#
+# test 6
+#
+./sort_cars -price < test1.in > test1.out
+cat > test1.expected <<EOF
+bmw 305i 120 50000
+bmw 305 100 45000
+fiat bravo 105 30000
+fiat 500 80 25000
+EOF
+if diff -q test1.out test1.expected; then
+    rm -f test1.out test1.expected
+else
+    echo "Test 6 FAILED"
+    diff test1.out test1.expected
+    exit 1
+fi
+rm -f test1.in
+#
+# test 7
+#
+(for x in `seq 1 200`; do for y in `seq 100 300`; do echo "maker$x model$y 1$x ${x}9$y"; done; done ) > test1.in
+./sort_cars +price < test1.in > test1.out
+sort -n -k 4 < test1.in > test1.expected
+if diff -q test1.out test1.expected; then
+    rm -f test1.out test1.expected
+else
+    echo "Test 7 FAILED"
+    diff test1.out test1.expected
+    exit 1
+fi
+rm -f test1.in
+echo PASSED