Feature/rhyme

HW5/rhyme/circularList/circularList.c

@@ -0,0 +1,77 @@
+#include "circularList.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+int addToList(int data, CircularList **head) {
+    CircularList *newNode = (CircularList *)malloc(sizeof(CircularList));
+    if (newNode == NULL)
+        return -1;
+
+    newNode->data = data;
+
+    if (*head == NULL) {
+        newNode->next = newNode;
+        *head = newNode;
+        return 0;
+    }
+
+    CircularList *current = *head;
+    while (current->next != *head)
+        current = current->next;
+    newNode->next = *head;
+    current->next = newNode;
+    return 0;
+}
+
+int removeFromList(int data, CircularList **head) {
+    if (*head == NULL)
+        return -1;
+
+    CircularList *current = *head;
+    CircularList *prev = NULL;
+
+    do {
+        if (current->data == data)
+            break;
+        prev = current;
+        current = current->next;
+    } while (current != *head);
+
+    if (current->data != data)
+        return -1;
+
+    if (current->next == current) {
+        free(current);
+        *head = NULL;
+        return 0;
+    }
+
+    if (current == *head) {
+        prev = *head;
+        while (prev->next != *head)
+            prev = prev->next;
+        *head = current->next;
+    }
+
+    prev->next = current->next;
+    free(current);
+    return 0;
+}
+
+void freeList(CircularList *head) {
+    if (head == NULL)
+        return;
+
+    CircularList *last = head;
+    while (last->next != head)
+        last = last->next;
+    last->next = NULL;
+
+    CircularList *current = head;
+    while (current != NULL) {
+        CircularList *next = current->next;
+        free(current);
+        current = next;
+    }
+}
+

HW5/rhyme/circularList/circularList.h

@@ -0,0 +1,29 @@
+#pragma once
+
+typedef struct CircularList {
+    int data;
+    struct CircularList *next;
+} CircularList;
+
+/**
+ * @brief Add element to list
+ * @param data Integer to add
+ * @param head Pointer to pointer of list head
+ * @return -1 if couldn't allocate memory, 0 otherwise
+ */
+int addToList(int data, CircularList **head);
+
+/**
+ * @brief Remove element from list
+ * @param data Integer to remove
+ * @param head Pointer to pointer of list head
+ * @return -1 if couldn't find element, 0 otherwise
+ */
+int removeFromList(int data, CircularList **head);
+
+/**
+ * @brief Free list data
+ * @param head Pointer to list head
+ */
+void freeList(CircularList *head);
+

HW5/rhyme/src/main.c

@@ -0,0 +1,74 @@
+#include "../circularList/circularList.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+int rhyme(int numWarrior, int numMurder);
+
+int main() {
+    int n = 41;
+    int m = 3;
+    int result = rhyme(n, m);
+    if (result != -1)
+        printf("Initial position should be: %d\n", result);
+
+    n = 1;
+    m = 1;
+    result = rhyme(n, m);
+    if (result != -1)
+        printf("Initial position should be: %d\n", result);
+
+    n = 2;
+    m = 2;
+    result = rhyme(n, m);
+    if (result != -1)
+        printf("Initial position should be: %d\n", result);
+
+    n = 7;
+    m = 3;
+    result = rhyme(n, m);
+    if (result != -1)
+        printf("Initial position should be: %d\n", result); 
+
+    return 0;
+}
+
+int rhyme(int numWarrior, int numMurder) {
+    if (numWarrior <= 0 || numMurder <= 0) {
+        printf("Incorrect initial data");
+        return -1;
+    }
+
+    CircularList *head = NULL;
+    for (int i = 1; i <= numWarrior; ++i) {
+        if (addToList(i, &head) == -1) {
+            printf("Couldn't allocate memory");
+            freeList(head);
+            return -1;
+        }
+    }
+
+    CircularList *prev = head;
+    while (prev->next != head)
+        prev = prev->next;
+
+    CircularList *current = head;
+
+    while (current->next != current) {
+        for (int i = 0; i < numMurder - 1; ++i) {
+            prev = current;
+            current = current->next;
+        }
+
+        prev->next = current->next;
+        if (current == head)
+            head = current->next;
+
+        CircularList *toDelete = current;
+        current = current->next;
+        free(toDelete);
+    }
+    int lastPos = current->data;
+    free(current);
+    return lastPos;
+}
+