Add pop-count (#940)

config.json

@@ -2,14 +2,14 @@
   "language": "C",
   "slug": "c",
   "active": true,
-  "blurb": "C is a small, general-purpose, imperative programming language with a static type system, scopes, and structures. It's typically used as an alternative to assembly programming, such as in operating systems.",
-  "version": 3,
   "status": {
     "concept_exercises": false,
     "test_runner": true,
     "representer": false,
     "analyzer": false
   },
+  "blurb": "C is a small, general-purpose, imperative programming language with a static type system, scopes, and structures. It's typically used as an alternative to assembly programming, such as in operating systems.",
+  "version": 3,
   "online_editor": {
     "indent_style": "space",
     "indent_size": 4,
@@ -36,7 +36,6 @@
     ]
   },
   "exercises": {
-    "concept": [],
     "practice": [
       {
         "slug": "hello-world",
@@ -1015,6 +1014,19 @@
           "performance_optimizations",
           "strings"
         ]
+      },
+      {
+        "slug": "pop-count",
+        "name": "Eliud's Eggs",
+        "uuid": "8a813e24-6263-437d-a610-7f5da1456b7f",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 2,
+        "topics": [
+          "bitwise_operations",
+          "control_flow_if_statements",
+          "control_flow_loops"
+        ]
       }
     ]
   },
@@ -1024,7 +1036,7 @@
       "slug": "basics",
       "name": "Basics"
     },
-    {    
+    {
       "uuid": "20948c69-20f7-498d-b743-fada00e5c79d",
       "slug": "bits",
       "name": "Bits"
@@ -1043,7 +1055,7 @@
       "uuid": "1721552b-9c55-432d-a776-05e618c25bb4",
       "slug": "function-pointers",
       "name": "Function Pointers"
-    },    
+    },
     {
       "uuid": "e5725455-3ce3-48e9-a3c6-ceb522434b5b",
       "slug": "conditionals",
@@ -1058,7 +1070,7 @@
       "uuid": "e39f5003-8ed9-4d82-ab9b-f79bbca78679",
       "slug": "linkage",
       "name": "Linkage"
-    },    
+    },
     {
       "uuid": "3d79388b-e909-4e1b-99e9-d28e30e54fde",
       "slug": "loops",
@@ -1083,7 +1095,7 @@
       "uuid": "f4946fe8-afb3-4110-8fca-b1476f19be6f",
       "slug": "static-functions",
       "name": "Static Functions"
-    },    
+    },
     {
       "uuid": "c065ddca-627c-45b6-a92f-7144dd852111",
       "slug": "storage-class-specifiers",
@@ -1092,46 +1104,46 @@
   ],
   "key_features": [
     {
-      "icon": "cross-platform",
       "title": "Cross-platform",
-      "content": "C is portable and can run on almost any platform and chipset."
+      "content": "C is portable and can run on almost any platform and chipset.",
+      "icon": "cross-platform"
     },
     {
-      "icon": "general-purpose",
       "title": "General purpose",
-      "content": "Can be used for a wide variety of workloads from IoT to game engines."
+      "content": "Can be used for a wide variety of workloads from IoT to game engines.",
+      "icon": "general-purpose"
     },
     {
-      "icon": "fast",
       "title": "Fast",
-      "content": "Consistently rated as one of the highest performing languages for energy and time."
+      "content": "Consistently rated as one of the highest performing languages for energy and time.",
+      "icon": "fast"
     },
     {
-      "icon": "stable",
       "title": "Stable",
-      "content": "The C standard values stability and backwards compatibility, C programs can run for decades."
+      "content": "The C standard values stability and backwards compatibility, C programs can run for decades.",
+      "icon": "stable"
     },
     {
-      "icon": "powerful",
       "title": "Powerful",
-      "content": "Allows both lower and higher level functionality, making it very powerful."
+      "content": "Allows both lower and higher level functionality, making it very powerful.",
+      "icon": "powerful"
     },
     {
-      "icon": "widely-used",
       "title": "Widely used",
-      "content": "Consistently one of the most popular languages for everything from operating systems to firmware"
+      "content": "Consistently one of the most popular languages for everything from operating systems to firmware",
+      "icon": "widely-used"
     }
   ],
   "tags": [
     "execution_mode/compiled",
     "paradigm/procedural",
-    "typing/static",
     "platform/android",
     "platform/ios",
     "platform/linux",
     "platform/mac",
     "platform/windows",
     "runtime/language_specific",
+    "typing/static",
     "used_for/backends",
     "used_for/cross_platform_development",
     "used_for/embedded_systems",

exercises/practice/pop-count/.docs/instructions.md

@@ -0,0 +1,8 @@
+# Instructions
+
+Your task is to count the number of 1 bits in the binary representation of a number.
+
+## Restrictions
+
+Keep your hands off that bit-count functionality provided by your standard library!
+Solve this one yourself using other basic tools instead.

exercises/practice/pop-count/.docs/introduction.md

@@ -0,0 +1,47 @@
+# Introduction
+
+Your friend Eliud inherited a farm from her grandma Tigist.
+Her granny was an inventor and had a tendency to build things in an overly complicated manner.
+The chicken coop has a digital display showing an encoded number representing the positions of all eggs that could be picked up.
+
+Eliud is asking you to write a program that shows the actual number of eggs in the coop.
+
+The position information encoding is calculated as follows:
+
+1. Scan the potential egg-laying spots and mark down a `1` for an existing egg or a `0` for an empty spot.
+2. Convert the number from binary to decimal.
+3. Show the result on the display.
+
+Example 1:
+
+```text
+Chicken Coop:
+ _ _ _ _ _ _ _
+|E| |E|E| | |E|
+
+Resulting Binary:
+ 1 0 1 1 0 0 1
+
+Decimal number on the display:
+89
+
+Actual eggs in the coop:
+4
+```
+
+Example 2:
+
+```text
+Chicken Coop:
+ _ _ _ _ _ _ _ _
+| | | |E| | | | |
+
+Resulting Binary:
+ 0 0 0 1 0 0 0 0
+
+Decimal number on the display:
+16
+
+Actual eggs in the coop:
+1
+```

exercises/practice/pop-count/.meta/config.json

@@ -0,0 +1,21 @@
+{
+  "authors": [
+    "ahans"
+  ],
+  "files": {
+    "solution": [
+      "pop_count.c",
+      "pop_count.h"
+    ],
+    "test": [
+      "test_pop_count.c"
+    ],
+    "example": [
+      ".meta/example.c",
+      ".meta/example.h"
+    ]
+  },
+  "blurb": "Help Eliud count the number of eggs in her chicken coop by counting the number of 1 bits in a binary representation.",
+  "source": "Christian Willner, Eric Willigers",
+  "source_url": "https://forum.exercism.org/t/new-exercise-suggestion-pop-count/7632/5"
+}

exercises/practice/pop-count/.meta/example.c

@@ -0,0 +1,11 @@
+#include "pop_count.h"
+
+int egg_count(int value)
+{
+   int count = 0;
+   while (value != 0) {
+      count += value & 1;
+      value = value >> 1;
+   }
+   return count;
+}

exercises/practice/pop-count/.meta/example.h

@@ -0,0 +1,6 @@
+#ifndef POP_COUNT_H
+#define POP_COUNT_H
+
+int egg_count(int value);
+
+#endif

exercises/practice/pop-count/.meta/tests.toml

@@ -0,0 +1,22 @@
+# 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.
+
+[559e789d-07d1-4422-9004-3b699f83bca3]
+description = "0 eggs"
+
+[97223282-f71e-490c-92f0-b3ec9e275aba]
+description = "1 egg"
+
+[1f8fd18f-26e9-4144-9a0e-57cdfc4f4ff5]
+description = "4 eggs"
+
+[0c18be92-a498-4ef2-bcbb-28ac4b06cb81]
+description = "13 eggs"

exercises/practice/pop-count/makefile

@@ -0,0 +1,37 @@
+### If you wish to use extra libraries (math.h for instance),
+### add their flags here (-lm in our case) in the "LIBS" variable.
+
+LIBS = -lm
+
+###
+CFLAGS  = -std=c99
+CFLAGS += -g
+CFLAGS += -Wall
+CFLAGS += -Wextra
+CFLAGS += -pedantic
+CFLAGS += -Werror
+CFLAGS += -Wmissing-declarations
+CFLAGS += -DUNITY_SUPPORT_64 -DUNITY_OUTPUT_COLOR
+
+ASANFLAGS  = -fsanitize=address
+ASANFLAGS += -fno-common
+ASANFLAGS += -fno-omit-frame-pointer
+
+.PHONY: test
+test: tests.out
+	@./tests.out
+
+.PHONY: memcheck
+memcheck: ./*.c ./*.h
+	@echo Compiling $@
+	@$(CC) $(ASANFLAGS) $(CFLAGS) test-framework/unity.c ./*.c -o memcheck.out $(LIBS)
+	@./memcheck.out
+	@echo "Memory check passed"
+
+.PHONY: clean
+clean:
+	rm -rf *.o *.out *.out.dSYM
+
+tests.out: ./*.c ./*.h
+	@echo Compiling $@
+	@$(CC) $(CFLAGS) test-framework/unity.c ./*.c -o tests.out $(LIBS)

exercises/practice/pop-count/pop_count.c

@@ -0,0 +1 @@
+#include "pop_count.h"

exercises/practice/pop-count/pop_count.h

@@ -0,0 +1,4 @@
+#ifndef POP_COUNT_H
+#define POP_COUNT_H
+
+#endif