Add resistor-color-duo (#113)

config.json

@@ -178,6 +178,14 @@
         "prerequisites": [],
         "difficulty": 3
       },
+      {
+        "slug": "resistor-color-duo",
+        "name": "Resistor Color Duo",
+        "uuid": "951a3e60-ce1d-4c08-b812-cd4198ed6fe1",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 3
+      },
       {
         "slug": "scrabble-score",
         "name": "Scrabble Score",

exercises/practice/resistor-color-duo/.docs/instructions.md

@@ -0,0 +1,33 @@
+# Instructions
+
+If you want to build something using a Raspberry Pi, you'll probably use _resistors_.
+For this exercise, you need to know two things about them:
+
+- Each resistor has a resistance value.
+- Resistors are small - so small in fact that if you printed the resistance value on them, it would be hard to read.
+
+To get around this problem, manufacturers print color-coded bands onto the resistors to denote their resistance values.
+Each band has a position and a numeric value.
+
+The first 2 bands of a resistor have a simple encoding scheme: each color maps to a single number.
+For example, if they printed a brown band (value 1) followed by a green band (value 5), it would translate to the number 15.
+
+In this exercise you are going to create a helpful program so that you don't have to remember the values of the bands.
+The program will take color names as input and output a two digit number, even if the input is more than two colors!
+
+The band colors are encoded as follows:
+
+- black: 0
+- brown: 1
+- red: 2
+- orange: 3
+- yellow: 4
+- green: 5
+- blue: 6
+- violet: 7
+- grey: 8
+- white: 9
+
+From the example above:
+brown-green should return 15, and
+brown-green-violet should return 15 too, ignoring the third color.

exercises/practice/resistor-color-duo/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "keiravillekode"
+  ],
+  "files": {
+    "solution": [
+      "resistor_color_duo.s"
+    ],
+    "test": [
+      "resistor_color_duo_test.c"
+    ],
+    "example": [
+      ".meta/example.s"
+    ]
+  },
+  "blurb": "Convert color codes, as used on resistors, to a numeric value.",
+  "source": "Maud de Vries, Erik Schierboom",
+  "source_url": "https://github.com/exercism/problem-specifications/issues/1464"
+}

exercises/practice/resistor-color-duo/.meta/example.s

@@ -0,0 +1,61 @@
+.data
+black:  .string "black"
+brown:  .string "brown"
+red:    .string "red"
+orange: .string "orange"
+yellow: .string "yellow"
+green:  .string "green"
+blue:   .string "blue"
+violet: .string "violet"
+grey:   .string "grey"
+white:  .string "white"
+
+color_array:
+        .dword black
+        .dword brown
+        .dword red
+        .dword orange
+        .dword yellow
+        .dword green
+        .dword blue
+        .dword violet
+        .dword grey
+        .dword white
+        .dword 0                        /* Sentinel value to indicate end of array */
+
+.text
+.globl value
+
+color_code:
+        adrp    x7, color_array
+        add     x7, x7, :lo12:color_array
+        mov     x2, x7
+
+.next:
+        mov     x3, x0
+        ldr     x4, [x2], #8            /* load pointer, post-increment */
+
+.compare:
+        ldrb    w5, [x3], #1            /* load character, post-increment */
+        ldrb    w6, [x4], #1            /* load character, post-increment */
+        cmp     w5, w6
+        bne     .next
+
+        cbnz    w5, .compare
+
+        sub     x2, x2, #8
+        sub     x0, x2, x7
+        lsr     x0, x0, #3
+        ret
+
+/* extern int value(const char *first, const char *second, const char *third); */
+value:
+        mov     x9, lr
+        bl      color_code
+        mov     x11, x0
+        mov     x0, x1
+        bl      color_code
+        mov     x10, #10
+        madd    x0, x10, x11, x0
+        mov     lr, x9
+        ret

exercises/practice/resistor-color-duo/.meta/tests.toml

@@ -0,0 +1,31 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[ce11995a-5b93-4950-a5e9-93423693b2fc]
+description = "Brown and black"
+
+[7bf82f7a-af23-48ba-a97d-38d59406a920]
+description = "Blue and grey"
+
+[f1886361-fdfd-4693-acf8-46726fe24e0c]
+description = "Yellow and violet"
+
+[b7a6cbd2-ae3c-470a-93eb-56670b305640]
+description = "White and red"
+
+[77a8293d-2a83-4016-b1af-991acc12b9fe]
+description = "Orange and orange"
+
+[0c4fb44f-db7c-4d03-afa8-054350f156a8]
+description = "Ignore additional colors"
+
+[4a8ceec5-0ab4-4904-88a4-daf953a5e818]
+description = "Black and brown, one-digit"

exercises/practice/resistor-color-duo/Makefile

@@ -0,0 +1,36 @@
+AS = aarch64-linux-gnu-as
+CC = aarch64-linux-gnu-gcc
+
+CFLAGS = -g -Wall -Wextra -pedantic -Werror
+LDFLAGS =
+
+ALL_LDFLAGS = -pie -Wl,--fatal-warnings
+
+ALL_CFLAGS = -std=c99 -fPIE $(CFLAGS)
+ALL_LDFLAGS += $(LDFLAGS)
+
+C_OBJS = $(patsubst %.c,%.o,$(wildcard *.c))
+AS_OBJS = $(patsubst %.s,%.o,$(wildcard *.s))
+ALL_OBJS = $(filter-out example.o,$(C_OBJS) $(AS_OBJS) vendor/unity.o)
+
+CC_CMD = $(CC) $(ALL_CFLAGS) -c -o $@ $<
+
+all: tests
+	qemu-aarch64 -L /usr/aarch64-linux-gnu ./$<
+
+tests: $(ALL_OBJS)
+	@$(CC) $(ALL_CFLAGS) $(ALL_LDFLAGS) -o $@ $(ALL_OBJS)
+
+%.o: %.s
+	@$(AS) -o $@ $<
+
+%.o: %.c
+	@$(CC_CMD)
+
+vendor/unity.o: vendor/unity.c vendor/unity.h vendor/unity_internals.h
+	@$(CC_CMD)
+
+clean:
+	@rm -f *.o vendor/*.o tests
+
+.PHONY: all clean

exercises/practice/resistor-color-duo/resistor_color_duo.s

@@ -0,0 +1,5 @@
+.text
+.globl value
+
+value:
+    ret

exercises/practice/resistor-color-duo/resistor_color_duo_test.c

@@ -0,0 +1,57 @@
+#include "vendor/unity.h"
+
+#include <stddef.h>
+
+extern int value(const char *first, const char *second, const char *third);
+
+void setUp(void) {
+}
+
+void tearDown(void) {
+}
+
+void test_brown_and_black(void) {
+    TEST_ASSERT_EQUAL_INT(10, value("brown", "black", NULL));
+}
+
+void test_blue_and_grey(void) {
+    TEST_IGNORE();
+    TEST_ASSERT_EQUAL_INT(68, value("blue", "grey", NULL));
+}
+
+void test_yellow_and_violet(void) {
+    TEST_IGNORE();
+    TEST_ASSERT_EQUAL_INT(47, value("yellow", "violet", NULL));
+}
+
+void test_white_and_red(void) {
+    TEST_IGNORE();
+    TEST_ASSERT_EQUAL_INT(92, value("white", "red", NULL));
+}
+
+void test_orange_and_orange(void) {
+    TEST_IGNORE();
+    TEST_ASSERT_EQUAL_INT(33, value("orange", "orange", NULL));
+}
+
+void test_ignore_additional_colors(void) {
+    TEST_IGNORE();
+    TEST_ASSERT_EQUAL_INT(51, value("green", "brown", "orange"));
+}
+
+void test_black_and_brown_onedigit(void) {
+    TEST_IGNORE();
+    TEST_ASSERT_EQUAL_INT(1, value("black", "brown", NULL));
+}
+
+int main(void) {
+    UNITY_BEGIN();
+    RUN_TEST(test_brown_and_black);
+    RUN_TEST(test_blue_and_grey);
+    RUN_TEST(test_yellow_and_violet);
+    RUN_TEST(test_white_and_red);
+    RUN_TEST(test_orange_and_orange);
+    RUN_TEST(test_ignore_additional_colors);
+    RUN_TEST(test_black_and_brown_onedigit);
+    return UNITY_END();
+}