Language: C

#include <string.h>
#include <stdio.h>
#include <stdlib.h>
struct Node {
    int key;
    struct Node *prev
	struct Node *next;
};
 
struct Node *note;
 
void insert(int key) {
    struct Node *x = (struct Node *)malloc(sizeof(struct Node));
    x->key = key;
	note->next->prev = x;
    x->next = note->next;
    note->next = x;
    x->prev = note;
}
 
struct Node* search(int key) {
    struct Node *x = note->next;
    while(x != note && x->key != key ) {
        x = x-> next;
    }
    return x;
}
 
void deleteNode(struct Node *x) {
    if (x == note) return;
    x->prev->next = x->next;
    x->next->prev = x->prev;
    free(x);
}
 
void deleteFirst() {
    deleteNode(note->next);
}
 
void deleteLast() {
    deleteNode(note->prev);
}
void deleteKey(int key) {
    deleteNode(search(key));
}
 
void print() {
    struct Node *x;
    x = note->next;
    int isf = 0;
    while(1) {
        if (x == note) break;
        if(isf++ > 0) printf(" ");
        printf("%d", x->key);
        x = x->next;
    }
    printf("\n");
}
 
 
int main(void) {
    int key, n;
    char order[20];
    scanf("%d", &n);
	note = (struct Node *)malloc(sizeof(struct Node));
    note->next = note;
    note->prev = note;
    for (int i = 0; i < n; i++) {
        scanf("%s%d",order, &key);
        if(order[0] == 'i') {
            insert(key);
        } 
    	if(com[0] == 'd') {
            if(strlen(order) < 6) {
            	deleateKey();
            }else if{
                if( order[6] == 'F') {
                    deleteFirst();
                }
            	if(com[6] == 'L') {
                    deleteLast();
                }
            }
    }
    print();
    return 0;
}

Compiler output:
main.c:7:9: error: expected ':', ',', ';', '}' or '__attribute__' before 'struct'
    7 |         struct Node *next;
      |         ^~~~~~
main.c: In function 'insert':
main.c:15:13: error: 'struct Node' has no member named 'next'
   15 |         note->next->prev = x;
      |             ^~
main.c:16:6: error: 'struct Node' has no member named 'next'
   16 |     x->next = note->next;
      |      ^~
main.c:16:19: error: 'struct Node' has no member named 'next'
   16 |     x->next = note->next;
      |                   ^~
main.c:17:9: error: 'struct Node' has no member named 'next'
   17 |     note->next = x;
      |         ^~
main.c:18:6: error: 'struct Node' has no member named 'prev'
   18 |     x->prev = note;
      |      ^~
main.c: In function 'search':
main.c:22:26: error: 'struct Node' has no member named 'next'
   22 |     struct Node *x = note->next;
      |                          ^~
main.c:24:14: error: 'struct Node' has no member named 'next'
   24 |         x = x-> next;
      |              ^~
main.c: In function 'deleteNode':
main.c:31:6: error: 'struct Node' has no member named 'prev'
   31 |     x->prev->next = x->next;
      |      ^~
main.c:31:22: error: 'struct Node' has no member named 'next'
   31 |     x->prev->next = x->next;
      |                      ^~
main.c:32:6: error: 'struct Node' has no member named 'next'
   32 |     x->next->prev = x->prev;
      |      ^~
main.c:32:22: error: 'struct Node' has no member named 'prev'
   32 |     x->next->prev = x->prev;
      |                      ^~
main.c: In function 'deleteFirst':
main.c:37:20: error: 'struct Node' has no member named 'next'
   37 |     deleteNode(note->next);
      |                    ^~
main.c: In function 'deleteLast':
main.c:41:20: error: 'struct Node' has no member named 'prev'
   41 |     deleteNode(note->prev);
      |                    ^~
main.c: In function 'print':
main.c:49:13: error: 'struct Node' has no member named 'next'
   49 |     x = note->next;
      |             ^~
main.c:55:14: error: 'struct Node' has no member named 'next'
   55 |         x = x->next;
      |              ^~
main.c: In function 'main':
main.c:66:9: error: 'struct Node' has no member named 'next'
   66 |     note->next = note;
      |         ^~
main.c:67:9: error: 'struct Node' has no member named 'prev'
   67 |     note->prev = note;
      |         ^~
main.c:73:12: error: 'com' undeclared (first use in this function)
   73 |         if(com[0] == 'd') {
      |            ^~~
main.c:73:12: note: each undeclared identifier is reported only once for each function it appears in
main.c:75:17: error: implicit declaration of function 'deleateKey'; did you mean 'deleteKey'? [-Wimplicit-function-declaration]
   75 |                 deleateKey();
      |                 ^~~~~~~~~~
      |                 deleteKey
main.c:76:21: error: expected '(' before '{' token
   76 |             }else if{
      |                     ^
      |                     (
main.c:87:1: error: expected declaration or statement at end of input
   87 | }
      | ^