Heterogeneous Linked List

heterogeneous_linked_list.cpp

// Program for creating a heterogeneous linked list
// BUGS: fails for strings e.g. abc -> a (b,c are not read)
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>

const int SIZE =  80;

typedef enum { INT, CHAR, FLOAT } Type;
typedef struct node__ {
	void* data;
	Type type;
	struct node__* next;
} Node;

Node* create_int (int data) {
	Node* temp = NULL;
	if ((temp=(Node*)malloc (sizeof (Node))) == NULL) {
		fprintf (stderr, "Node creation failed in %s for data %d", __func__,  data);
		return NULL;
	}

	temp->data = malloc (sizeof(int));
	*(int*)(temp->data) = data;
	temp->type = INT;
	temp->next = NULL;

	return temp;
}

Node* create_char (char data) {
	Node* temp = NULL;
	if ((temp=(Node*)malloc (sizeof (Node))) == NULL) {
		fprintf (stderr, "Node creation failed in %s for data %c", __func__,  data);
		return NULL;
	}

	temp->data = malloc (sizeof(int));
	*(char*)(temp->data) = data;
	temp->type = CHAR;
	temp->next = NULL;

	return temp;
}

Node* create_float (float data) {
	Node* temp = NULL;
	if ((temp=(Node*)malloc (sizeof (Node))) == NULL) {
		fprintf (stderr, "Node creation failed in %s for data %f", __func__,  data);
		return NULL;
	}

	temp->data = malloc (sizeof(int));
	*(float*)(temp->data) = data;
	temp->type = FLOAT;
	temp->next = NULL;

	return temp;
}

Node* append_node (Node* front, Node* node) {
	if (front == NULL) {
		front = node;
	}
	else {
		Node* temp = front;
		while (temp->next != NULL)
			temp = temp->next;

		temp->next = node;
	}

	return front;
}

void print_list (Node* front) {
	Node* temp = NULL;
	for (temp = front; temp != NULL; temp = temp->next) {
	       switch (temp->type) {
			case INT:
		 		printf ("%d ", *(int*)temp->data);
				break;
			case CHAR:
				printf ("%c ", *(char*)temp->data);
				break;
			case FLOAT:
				printf ("%g ", *(float*)temp->data);
				break;
	       }
	}
	putchar ('\n');
}


int main () {
	Node* front;
	char str[SIZE];
	int i;
	char c;

	while (scanf("%s", str) > 0) {
		if (isalpha (str[0])) {
			front = append_node (front, create_char (str[0]));
		}
		else if (sscanf (str, "%d %c", &i, &c) > 0 && c == '.') {
			front = append_node (front, create_float (strtof (str, NULL)));
		}
		else {
			front = append_node (front, create_int (atoi(str)));
		}
	}

	print_list (front);

	return 0;
}