Done with the program

calloc was used here

.vscode/launch.json

@@ -0,0 +1,33 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "(gdb) Launch",
+            "type": "cppdbg",
+            "request": "launch",
+            "program": "${workspaceFolder}/customer_list",
+            "args": [],
+            "stopAtEntry": false,
+            "cwd": "${fileDirname}",
+            "environment": [],
+            "externalConsole": false,
+            "MIMode": "gdb",
+            "setupCommands": [
+                {
+                    "description": "Enable pretty-printing for gdb",
+                    "text": "-enable-pretty-printing",
+                    "ignoreFailures": true
+                },
+                {
+                    "description": "Set Disassembly Flavor to Intel",
+                    "text": "-gdb-set disassembly-flavor intel",
+                    "ignoreFailures": true
+                }
+            ]
+        }
+
+    ]
+}

.vscode/tasks.json

@@ -0,0 +1,28 @@
+{
+    "tasks": [
+        {
+            "type": "cppbuild",
+            "label": "C/C++: gcc build active file",
+            "command": "/usr/bin/gcc",
+            "args": [
+                "-fdiagnostics-color=always",
+                "-g",
+                "${file}",
+                "-o",
+                "${fileDirname}/${fileBasenameNoExtension}"
+            ],
+            "options": {
+                "cwd": "${fileDirname}"
+            },
+            "problemMatcher": [
+                "$gcc"
+            ],
+            "group": {
+                "kind": "build",
+                "isDefault": true
+            },
+            "detail": "Task generated by Debugger."
+        }
+    ],
+    "version": "2.0.0"
+}

customer_list.c

@@ -1,6 +1,6 @@
 /*----------------------------------------------------------
  *				HTBLA-Leonding, 2. JG
- *              */  your name /*
+ *              Marc Tismonar
  * ---------------------------------------------------------
  * Description:
  * Implementation of customer_list.h.
@@ -11,4 +11,242 @@
 #include <stdlib.h>
 #include <string.h>
 #include <stdbool.h>
+#include "customer_list.h"
 
+//redefine NULL, bc Mr. Schraml said that its not safe
+#ifdef NULL
+#undef NULL
+#define NULL 0
+#endif
+
+struct CustomerListEntryData {
+    int id;
+    const char* name;
+    int revenue;
+};
+
+struct CustomerListData {
+    int length;
+    CustomerListEntry customers[MAX_LIST_ENTRIES];
+};
+
+static CustomerList staticCl;
+
+
+CustomerList init_customer_list() {
+    staticCl = (CustomerList)calloc(1, sizeof(struct CustomerListData)); //using calloc :) it initializes the memory with 0
+    return staticCl;
+}
+
+int get_length(const CustomerList cl) {
+    if (cl == 0) {
+        return -1;
+    }
+    return cl->length;
+}
+
+CustomerListEntry create_customer(int id, const char* customer_name, int revenue) {
+    if (id < 0 || customer_name == 0 || revenue < 0) {
+        return 0;
+    }
+
+    CustomerListEntry new_customer = (CustomerListEntry)calloc(1, sizeof(struct CustomerListEntryData));
+    if (new_customer == 0) {
+        return 0;
+    }
+    new_customer->id = id;
+    new_customer->name = customer_name;
+    new_customer->revenue = revenue;
+    return new_customer;
+}
+
+bool add_customer(CustomerList cl, int id, const char* customer_name, int revenue) {
+    if (cl == 0 || id < 0 || customer_name == 0 || revenue < 0) {
+        return false;
+    }
+    
+    //check if the customer list is full
+    if (cl->length >= MAX_LIST_ENTRIES) {
+        return false;
+    }
+
+    //check if its already in the list
+    for (int i = 0; i < cl->length; i++) {
+        if (cl->customers[i]->id == id) {
+            return false;
+        }
+    }
+
+    CustomerListEntry new_customer = create_customer(id, customer_name, revenue);
+    if (new_customer == 0) {
+        return false;
+    }
+    cl->customers[cl->length] = new_customer;
+    cl->length++;
+    return true;
+}
+
+bool add_customers(CustomerList cl, CustomerListEntry e[], int n) {
+    if (cl == 0 || e == 0 || n < 0) {
+        return false;
+    }
+
+    //check if customer list is full
+    if (cl->length + n > MAX_LIST_ENTRIES) {
+        return false;
+    }
+
+    for (int i = 0; i < n; i++) {
+        // null check
+        if (e[i] == 0) {
+            return false;
+        }
+
+        //duplication check
+        for (int j = 0; j < cl->length; j++) {
+            if (cl->customers[j]->id == e[i]->id) {
+                return false;
+            }
+        }
+        cl->customers[cl->length] = e[i];
+        cl->length++;
+    }
+    return true;
+}
+
+CustomerListEntry get_customer_with_index(const CustomerList cl, int index) {
+    if (cl == 0 || index < 0 || index >= cl->length) {
+        return 0;
+    }
+    return cl->customers[index];
+}
+
+CustomerListEntry get_customer_with_id(const CustomerList cl, int id) {
+    if (cl == 0 || id < 0) {
+        return 0;
+    }
+
+    for (int i = 0; i < cl->length; i++) {
+        if (cl->customers[i]->id == id) {
+            return cl->customers[i];
+        }
+    }
+    return 0;
+}
+
+int get_customers_with_revenue(const CustomerList cl, int lower_bound, int upper_bound, CustomerListEntry result_list[], int result_len) {
+    if (cl == 0 || lower_bound < 0 || upper_bound < 0 || lower_bound > upper_bound || result_list == 0 || result_len < 0) {
+        return 0;
+    }
+    int result_count = 0;
+
+    //go through customer list & check if revenue is in bounds
+    for (int i = 0; i < cl->length; i++) {
+        if (cl->customers[i]->revenue >= lower_bound && cl->customers[i]->revenue <= upper_bound) {
+            if (result_count < result_len) {
+                result_list[result_count] = cl->customers[i];
+            }
+            result_count++;
+        }
+    }
+    return result_count;
+}
+
+CustomerListEntry get_customer_with_highest_revenue(const CustomerList cl) {
+    if (cl == 0) {
+        return 0;
+    }
+    CustomerListEntry highest_revenue_customer = cl->customers[0];
+
+    //go through customer list & return with highest revenue
+    for (int i = 1; i < cl->length; i++) {
+        if (cl->customers[i]->revenue > highest_revenue_customer->revenue) {
+            highest_revenue_customer = cl->customers[i];
+        }
+    }
+    return highest_revenue_customer;
+}
+
+CustomerListEntry get_customer_with_lowest_revenue(const CustomerList cl) {
+    if (cl == 0) {
+        return 0;
+    }
+    CustomerListEntry lowest_revenue_customer = cl->customers[0];
+
+    //go through customer list & return with lowest revenue
+    for (int i = 1; i < cl->length; i++) {
+        if (cl->customers[i]->revenue < lowest_revenue_customer->revenue) {
+            lowest_revenue_customer = cl->customers[i];
+        }
+    }
+    return lowest_revenue_customer;
+}
+
+int get_top_n_customers_revenue(const CustomerList cl, int n, CustomerListEntry result_list[]) {
+    if (cl == 0 || n <= 0 || result_list == 0) {
+        return 0;
+    }
+    
+    // make a copy of customer list
+    CustomerListEntry temp_list[MAX_LIST_ENTRIES];
+    for (int i = 0; i < cl->length; i++) {
+        temp_list[i] = cl->customers[i];
+    }
+
+    // sort the copy of customer list descending
+    for (int i = 0; i < cl->length - 1; i++) {
+        for (int j = i + 1; j < cl->length; j++) {
+            if (temp_list[i]->revenue < temp_list[j]->revenue) {
+                CustomerListEntry temp = temp_list[i];
+                temp_list[i] = temp_list[j];
+                temp_list[j] = temp;
+            }
+        }
+    }
+
+    // copy the n top customers to result_list
+    int result_count = n < cl->length ? n : cl->length;
+    for (int i = 0; i < result_count; i++) {
+        result_list[i] = temp_list[i];
+    }
+
+    return result_count;
+}
+
+int get_bottom_n_customers_revenue(const CustomerList cl, int n, CustomerListEntry result_list[]) {
+    if (cl == 0 || n <= 0 || result_list == 0) {
+        return 0;
+    }
+    
+    // make a copy of customer list
+    CustomerListEntry temp_list[MAX_LIST_ENTRIES];
+    for (int i = 0; i < cl->length; i++) {
+        temp_list[i] = cl->customers[i];
+    }
+
+    // sort the copy of customer list ascending
+    for (int i = 0; i < cl->length - 1; i++) {
+        for (int j = i + 1; j < cl->length; j++) {
+            if (temp_list[i]->revenue > temp_list[j]->revenue) {
+                CustomerListEntry temp = temp_list[i];
+                temp_list[i] = temp_list[j];
+                temp_list[j] = temp;
+            }
+        }
+    }
+
+    // copy the n bottom customers to result_list
+    int result_count = n < cl->length ? n : cl->length;
+    for (int i = 0; i < result_count; i++) {
+        result_list[i] = temp_list[i];
+    }
+
+    return result_count;
+}
+
+int get_customer_id(const CustomerListEntry customer) {
+    if (customer == 0) {
+        return -1;
+    }
+    return customer->id;
+}

customer_list.h

@@ -1,12 +1,13 @@
 /*----------------------------------------------------------
  *				HTBLA-Leonding, 2. JG
- *              */  your name /*
+ *              Marc Tismonar
  * ---------------------------------------------------------
  * Defines an abstract data type for managing a list of customers.
  * ----------------------------------------------------------
  */
 
-// TODO Don't miss the include guards!
+#ifndef __CUSTOMER_LIST_H
+#define __CUSTOMER_LIST_H
 
 #include <stdbool.h>
 
@@ -15,14 +16,13 @@
  * number of list entries.
  */
 
-// TODO: Define a symbolic constant named 'MAX_LIST_ENTRIES' for 13 customers
+#define MAX_LIST_ENTRIES 13
 
 /**
  * A CustomerListEntry consists of a unique customer ID, a name, 
  * and the revenue (in €1000) associated with this customer.
  */
-
+typedef struct CustomerListEntryData* CustomerListEntry;
-// TODO Declare the 'public' data type of the list entry
 
 /**
  * The CustomerList stores the number of currently saved customer list 
@@ -30,20 +30,19 @@
  * @remark Memory for the customer list entries must be provided by the caller. 
  * The `customers` array only manages references to customer list entries.
  */
-
+typedef struct CustomerListData* CustomerList;
-// TODO Declare the 'public' data type of the list entry
 
 /**
  * Provides the initialized empty instance of the customer list.
  * @return The customer list instance.
  */
-<type> init_customer_list();
+CustomerList init_customer_list();
 
 /**
  * @param cl The customer list data.
  * @return The number of entries in `cl` or a value less than zero if the list is invalid.
  */
-<type> get_length(<params>);
+int get_length(const CustomerList cl);
 
 /**
  * Creates an entry for a single customer.
@@ -52,7 +51,7 @@
  * @param revenue The revenue generated by that customer, in units of € 1000,-- (k€).
  * @return The entry if it could be created, else a null-entry (0).
  */
-<type> create_customer(<params>);
+CustomerListEntry create_customer(int id, const char* customer_name, int revenue);
 
 /**
  * Adds an entry to the customer list. If the list is already full OR a customer
@@ -65,7 +64,7 @@
  * @return `true` if the addition was successful, `false` otherwise.
  * @see add_customers
  */
-<type> add_customer(<params>);
+bool add_customer(CustomerList cl, int id, const char* customer_name, int revenue);
 
 /**
  * Adds `n` entries to the customer list. If the customer list cannot accommodate
@@ -81,7 +80,7 @@
  * included in the list.
  * @see add_customer
  */
-<type> add_customers(<params>);
+bool add_customers(CustomerList cl, CustomerListEntry e[], int n);
 
 /**
  * Provides the customer with a specific index within the list.
@@ -89,7 +88,7 @@
  * @param index The index of the requested customer.
  * @return The entry of the customer with the given index or null.
  */
-<type> get_customer_with_index(<params>);
+CustomerListEntry get_customer_with_index(const CustomerList cl, int index);
 
 /**
  * Searches for a customer with a specific ID.
@@ -97,7 +96,7 @@
  * @param id The unique customer ID to search for.
  * @return The entry of the customer with the given ID or null.
  */
-<type> get_customer_with_id(<params>);
+CustomerListEntry get_customer_with_id(const CustomerList cl, int id);
 
 /**
  * Searches for customers within specific revenue bounds and returns them in the 
@@ -109,7 +108,7 @@
  * @param result_len The maximum number of entries that can be stored in the result list.
  * @return The number of entries found.
  */
-<type> get_customers_with_revenue(<params>);
+int get_customers_with_revenue(const CustomerList cl, int lower_bound, int upper_bound, CustomerListEntry result_list[], int result_len);
 
 /**
  * Finds the customer with the highest revenue. If multiple customers have the 
@@ -117,7 +116,7 @@
  * @param cl The customer list data.
  * @return The customer with the highest revenue.
  */
-<type> get_customer_with_highest_revenue(<params>);
+CustomerListEntry get_customer_with_highest_revenue(const CustomerList cl);
 
 /**
  * Finds the customer with the lowest revenue. If multiple customers have the 
@@ -125,7 +124,7 @@
  * @param cl The customer list data.
  * @return The customer with the lowest revenue.
  */
-<type> get_customer_with_lowest_revenue(<params>);
+CustomerListEntry get_customer_with_lowest_revenue(const CustomerList cl);
 
 /**
  * Finds the `n` customers with the highest revenue. If multiple customers satisfy
@@ -140,7 +139,7 @@
  * @warning It is not verified whether `result_list` has sufficient size. If the size 
  * of `result_list` is smaller than `n`, the function may crash due to memory issues.
  */
-<type> get_top_n_customers_revenue(<params>);
+int get_top_n_customers_revenue(const CustomerList cl, int n, CustomerListEntry result_list[]);
 
 /**
  * Finds the `n` customers with the lowest revenue. If multiple customers satisfy
@@ -155,7 +154,7 @@
  * @warning It is not verified whether `result_list` has sufficient size. If the size 
  * of `result_list` is smaller than `n`, the function may crash due to memory issues.
  */
-<type> get_bottom_n_customers_revenue(<params>);
+int get_bottom_n_customers_revenue(const CustomerList cl, int n, CustomerListEntry result_list[]);
 
 /**
  * @brief Provides the ID of the given customer.
@@ -163,4 +162,6 @@
  * @return The ID of this customer or a value less than 0,
  * if the given customer is invalid.
  */
-<type> get_customer_id(<params>);
+int get_customer_id(const CustomerListEntry customer);
+
+#endif

makefile

@@ -1,8 +1,8 @@
 CC			= g++
 CCLINK		= g++
 LIBS		=
-CCOPTIONS	= -Wall -pedantic -g
+CCOPTIONS	= -Wall -pedantic -g -O0
-LDOPTIONS	=
+LDOPTIONS	= -g -O0
 HDRS		= customer_list.h test_customer_list.h
 
 TEST = customer_list
@@ -68,5 +68,5 @@ assignmentfolder:
 	rm ../assignment/*.assignment
 	make cleanall
 
-%.o: %.cpp $(HDRS)
+%.o: %.c $(HDRS)
 	$(CC) $(CCOPTIONS) -c $<