davinci-002_01 (Autopilot) list.c

Mean logprob: -0.3077343741348135 (73.51%)
Legend: 0%100%

#include <stdio.h> 
#include <stdlib.h>
#include <getopt.h>
#include <string.h>
#include "list.h"

#ifdef UNIT_TESTING
/* Redirect printf to a function in the test application so it's possible to
 * test the standard output. You can ignore this; it's not relevant to the
 * assignment. */
#ifdef printf
#undef printf
#endif /* printf */
extern int test_printf(const char *format,...);
#define printf test_printf
#endif

#define MAX_ITEM_PRINT_LEN 100

// Note: All list_ functions return a status code EXIT_FAILURE or EXIT_SUCCESS
// to indicate whether the operation was successful or not.

// Members of the node struct:
// char* item_name, float price, int quantity, node *next

// create a new list
int list_init(node **head) {
	*head = NULL;
	return EXIT_SUCCESS;
}

// print a single list item to an externally allocated string
// This should be in the format of:
// "quantity * item_name @ $price ea", where item_name is a string and 
// price is a float formatted with 2 decimal places.
int list_item_to_string(node *head, char *str) {
	if (head == NULL) {
		return EXIT_FAILURE;
	}
	if (str == NULL) {
		return EXIT_FAILURE;
	}
	char price[MAX_ITEM_PRINT_LEN];
	sprintf(price, "%.2f", head->price);
	snprintf(str, MAX_ITEM_PRINT_LEN, "%d * %s @ $%s ea", head->quantity, head->item_name, price);
	return EXIT_SUCCESS;
}

// print the list to stdout
// This should be in the format of:
// "pos: quantity * item_name @ $price ea", where 
//   pos is the position of the item in the list, 
//   item_name is the item_name of the item and 
//   price is the float price of the item formatted with 2 decimal places.
// For example:
// """1: 3 * banana @ $1.00 ea
// 2: 2 * orange @ $2.00 ea
// 3: 4 * apple @ $3.00 ea
// """
// It should return a newline character at the end of each item. 
// It should not have a leading newline character.
int list_print(node *head) {
	if (head == NULL) {
		return EXIT_FAILURE;
	}
	int pos = 1;
	node *current = head;
	while (current!= NULL) {
		char str[MAX_ITEM_PRINT_LEN];
		if (list_item_to_string(current, str) == EXIT_FAILURE) {
			return EXIT_FAILURE;
		}
		printf("%d: %s\n", pos, str);
		current = current->next;
		pos += 1;
	}
	return EXIT_SUCCESS;
}

// add a new item (name, price, quantity) to the list at position pos, 
//   such that the added item is the item at position pos
// For example:
// If the list is:
// 1: 3 * banana @ $1.00 ea
// 2: 2 * orange @ $2.00 ea
// and you call list_add_item_at_pos(&head, "apple", 3.0, 4, 2)
// the list should be:
// 1: 3 * banana @ $1.00 ea
// 2: 4 * apple @ $3.00 ea
// 3: 2 * orange @ $2.00 ea
int list_add_item_at_pos(node **head, char *item_name, float price, int quantity, unsigned int pos) {
	if (item_name == NULL) {
		return EXIT_FAILURE;
	}
	if (price < 0) {
		return EXIT_FAILURE;
	}
	if (quantity < 0) {
		return EXIT_FAILURE;
	}
	if (pos < 1) {
		return EXIT_FAILURE;
	}

	if (*head == NULL) {
		if (pos!= 1) {
			return EXIT_FAILURE;
		}
		node *new_node = malloc(sizeof(node));
		new_node->item_name = malloc((strlen(item_name) + 1) * sizeof(char));
		strcpy(new_node->item_name, item_name);
		new_node->price = price;
		new_node->quantity = quantity;
		new_node->next = NULL;
		*head = new_node;
		return EXIT_SUCCESS;
	}
	unsigned int current_pos = 1;
	node *current = *head;
	while (current->next!= NULL && current_pos < pos - 1) {
		current = current->next;
		current_pos += 1;
	}
	if (current_pos!= pos - 1) {
		return EXIT_FAILURE;
	}
	node *new_node = malloc(sizeof(node));
	new_node->item_name = malloc((strlen(item_name) + 1) * sizeof(char));
	strcpy(new_node->item_name, item_name);
	new_node->price = price;
	new_node->quantity = quantity;
	new_node->next = current->next;
	current->next = new_node;
	return EXIT_SUCCESS;
}

// update the item at position pos
int list_update_item_at_pos(node **head, char *item_name, float price, int quantity, unsigned int pos) {
	if (pos < 1) {
		return EXIT_FAILURE;
	}
	if (item_name == NULL) {
		return EXIT_FAILURE;
	}
	if (price < 0) {
		return EXIT_FAILURE;
	}
	if (quantity < 0) {
		return EXIT_FAILURE;
	}

	if (*head == NULL) {
		return EXIT_FAILURE;
	}
	unsigned int current_pos = 1;
	node *current = *head;
	while (current->next!= NULL && current_pos < pos) {
		current = current->next;
		current_pos += 1;
	}
	if (current_pos!= pos) {
		return EXIT_FAILURE;
	}
	free(current->item_name);
	current->item_name = malloc((strlen(item_name) + 1) * sizeof(char));
	strcpy(current->item_name, item_name);
	current->price = price;
	current->quantity = quantity;
	return EXIT_SUCCESS;
}

// remove the item at position pos
int list_remove_item_at_pos(node **head, int pos) {
	if (pos < 1) {
		return EXIT_FAILURE;
	}

	if (*head == NULL) {
		return EXIT_FAILURE;
	}
	if (pos == 1) {
		node *removed_node = *head;
		*head = (*head)->next;
		free(removed_node->item_name);
		free(removed_node);
		return EXIT_SUCCESS;
	}
	unsigned int current_pos = 1;
	node *current = *head;
	while (current->next!= NULL && current_pos < pos - 1) {
		current = current->next;
		current_pos += 1;
	}
	if (current_pos!= pos - 1) {
		return EXIT_FAILURE;
	}
	node *removed_node = current->next;
	current->next = current->next->next;
	free(removed_node->item_name);
	free(removed_node);
	return EXIT_SUCCESS;
}

// swap the item at position pos1 with the item at position pos2
int list_swap_item_positions(node **head, int pos1, int pos2) {
	if (pos1 < 1 || pos2 < 1) {
		return EXIT_FAILURE;
	}

	if (*head == NULL) {
		return EXIT_FAILURE;
	}
	if (pos1 == 1 && pos2 == 2) {
		node *temp = (*head)->next;
		(*head)->next = temp->next;
		temp->next = *head;
		*head = temp;
		return EXIT_SUCCESS;
	}
	unsigned int current_pos = 1;
	node *current = *head;
	while (current->next!= NULL && current_pos < pos1 - 1) {
		current = current->next;
		current_pos += 1;
	}
	if (current_pos!= pos1 - 1) {
		return EXIT_FAILURE;
	}
	node *node1 = current->next;
	node *node2 = node1->next;
	while (node2!= NULL && current_pos < pos2 - 1) {
		node2 = node2->next;
		current_pos += 1;
	}
	if (current_pos!= pos2 - 1) {
		return EXIT_FAILURE;
	}
	if (pos1 == 1) {
		current->next = node2->next;
		node2->next = node1;
		node1->next = current->next;
		*head = node2;
		return EXIT_SUCCESS;
	}
	if (pos2 == 1) {
		current->next = node2->next;
		node2->next = node1;
		node1->next = current->next;
		*head = node1;
		return EXIT_SUCCESS;
	}
	current->next = node2;
	node *temp = node1->next;
	node1->next = node2->next;
	node2->next = temp;
	return EXIT_SUCCESS;
}

// find the item position with the highest single price
int list_find_highest_price_item_position(node *head, int *pos) {
	if (head == NULL) {
		return EXIT_FAILURE;
	}
	node *current = head;
	float highest_price = head->price;
	int highest_price_pos = 1;
	int current_pos = 1;
	while (current->next!= NULL) {
		current = current->next;
		current_pos += 1;
		if (current->price > highest_price) {
			highest_price = current->price;
			highest_price_pos = current_pos;
		}
	}
	*pos = highest_price_pos;
	return EXIT_SUCCESS;
}

// calculate the total cost of the list (sum of all prices * quantities)
int list_cost_sum(node *head, float *total) {
	if (head == NULL) {
		return EXIT_FAILURE;
	}
	node *current = head;
	*total = 0;
	while (current!= NULL) {
		*total += current->price * current->quantity;
		current = current->next;
	}
	return EXIT_SUCCESS;
}

// save the list to file filename
// the file should be in the following format:
// item_name,price,quantity\n 
//   (one item per line, separated by commas, and newline at the end)
int list_save(node *head, char *filename) {
	if (head == NULL) {
		return EXIT_FAILURE;
	}
	if (filename == NULL) {
		return EXIT_FAILURE;
	}

	FILE *file = fopen(filename, "w");
	if (file == NULL) {
		return EXIT_FAILURE;
	}
	node *current = head;
	while (current!= NULL) {
		// char *item_name, float price, int quantity, node *next
		fprintf(file, "%s,%f,%d\n", current->item_name, current->price, current->quantity);
		current = current->next;
	}
	fclose(file);
	return EXIT_SUCCESS;
}

// load the list from file filename
// the file should be in the following format:
// item_name,price,quantity\n 
//   (one item per line, separated by commas, and newline at the end)
// the loaded values are added to the end of the list
int list_load(node **head, char *filename) {
	if (filename == NULL) {
		return EXIT_FAILURE;
	}

	FILE *file = fopen(filename, "r");
	if (file == NULL) {
		return EXIT_FAILURE;
	}
	char line[MAX_ITEM_PRINT_LEN];
	unsigned int line_num = 1;
	while (fgets(line, MAX_ITEM_PRINT_LEN, file)!= NULL) {
		// item_name,price,quantity\n 
		char *item_name = strtok(line, ",");
		if (item_name == NULL) {
			fclose(file);
			return EXIT_FAILURE;
		}
		char *price_string = strtok(NULL, ",");
		if (price_string == NULL) {
			fclose(file);
			return EXIT_FAILURE;
		}
		float price = atof(price_string);
		char *quantity_string = strtok(NULL, ",");
		if (quantity_string == NULL) {
			fclose(file);
			return EXIT_FAILURE;
		}
		int quantity = atoi(quantity_string);
		if (list_add_item_at_pos(head, item_name, price, quantity, line_num) == EXIT_FAILURE) {
			fclose(file);
			return EXIT_FAILURE;
		}
		line_num += 1;
	}
	fclose(file);
	return EXIT_SUCCESS;
}

// de-duplicate the list by combining items with the same name 
//    by adding their quantities
// The order of the returned list is undefined and may be in any order
int list_deduplicate(node **head) {
	if (*head == NULL) {
		return EXIT_FAILURE;
	}
	node *current = *head;
	while (current->next!= NULL) {
		node *next = current->next;
		while (next!= NULL) {
			if (strcmp(current->item_name, next->item_name)== 0) {
				current->quantity += next->quantity;
				list_remove_item_at_pos(head, 2);
			}
			next = next->next;
		}
		current = current->next;
	}
	return EXIT_SUCCESS;
}