Inserting elements at the beginning of a linked list (c) - c

Question

I am trying to create a linked list with various options and, unfortunately, stuck at the process of inserting elements(hour and minute) at the beginning of a linked list.
My code is:
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
typedef struct node{
int hour, minute;
struct node* next;
}node;
void insert_beginning (node** root1, node** root2, int value) {
node* new_node = malloc(sizeof(node));
if (new_node == NULL) {
exit(1);
}
new_node->hour = value;
new_node->next = *root1;
new_node->minute = value;
new_node->next = *root2;
*root1 = new_node;
*root2 = new_node;
}
int main (int argc, char* argv[]) {
int option = 0;
node* root = NULL;
printf("Choose option: \n");
printf("1. Add time to the list. \n");
printf("2. Delete time from the list. \n");
printf("3. Change the postion of the bisst and the smallest elements. \n");
printf("4. Write the list. \n");
printf("5. Delete the list. \n");
printf("Your option: ");
scanf("%i", &option);
if (option == '1')
{
node* root1 = NULL;
node* root2 = NULL;
insert_beginning(&root1, &root2, 12, 15);
insert_beginning(&root1, &root2, 13, 20);
insert_beginning(&root1, &root2, 14, 25);
for (node* curr = root; curr != NULL; curr = curr->next)
{
printf("%d:%d\n", curr->hour, curr->minute);
}
}
return 0;
}
My problem is in these lines (I think):
insert_beginning(&root1, &root2, 12, 15);
insert_beginning(&root1, &root2, 13, 20);
insert_beginning(&root1, &root2, 14, 25);
**too many arguments to function call, expected 3, have 4**
But also I am afraid it does not compile from the beginning. (An example):
Choose option:
1. Add time to the list.
2. Delete time from the list.
3. Change the postion of the bisst and the smallest elements.
4. Write the list.
5. Delete the list.
Your option: 1
Saving session...
...copying shared history...
...saving history...truncating history files...
...completed.
The goal is to receive a linked list like this (example):
Choose option:
1. Add time to the list.
2. Delete time from the list.
3. Change the postion of the bisst and the smallest elements.
4. Write the list.
5. Delete the list.
Your option: 1
14:25
13:20
12:15
I would highly appreciate your help!

Answer 1

Your program doesn't compile as insert_beginning() takes two node ** and a value but you call it with 4 arguments as noted by your compiler. You probably want 3 arguments node **, int hour and int minute.
You read int option but compare it against the character value ('1').
You have 3 root variables main(). You probably only want one.
In you first call *root1 and *root2 are NULL which will cause a segfault when you dereference those.
Always check the return value of scanf() otherwise you may be operating on uninitialized values. In your code you actually initialize option = 0 but your prompts suggest that you don't handle that case.
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
typedef struct node{
int hour;
int minute;
struct node* next;
} node;
void insert_beginning (node** root, int hour, int minute) {
node* new_node = malloc(sizeof(node));
if (!new_node) {
exit(1);
}
new_node->hour = hour;
new_node->minute = minute;
if(!*root) {
*root = new_node;
(*root)->next = NULL;
return;
}
new_node->next = *root;
*root = new_node;
}
int main (int argc, char* argv[]) {
node* root = NULL;
printf("Choose option: \n");
printf("1. Add time to the list. \n");
printf("2. Delete time from the list. \n");
printf("3. Change the postion of the bisst and the smallest elements. \n");
printf("4. Write the list. \n");
printf("5. Delete the list. \n");
printf("Your option: ");
int option;
if(scanf("%i", &option) != 1) {
printf("scanf failed\n");
exit(1);
}
if (option == 1) {
insert_beginning(&root, 12, 15);
insert_beginning(&root, 13, 20);
insert_beginning(&root, 14, 25);
for (node* curr = root; curr; curr = curr->next) {
printf("%d:%d\n", curr->hour, curr->minute);
}
}
}
and example output (note last in first out order as implies by "insert_beginning"):
Choose option:
1. Add time to the list.
2. Delete time from the list.
3. Change the postion of the bisst and the smallest elements.
4. Write the list.
5. Delete the list.
Your option: 1
14:25
13:20
12:15