user: Please show me the C implementation that matches the assembly code listed below:

```asm
<main>:
  endbr64
  push   %r15
  lea    D27(%rip),%r15
  push   %r14
  lea    D32(%rip),%r14
  push   %r13
  lea    D36(%rip),%r13
  push   %r12
  push   %rbp
  xor    %ebp,%ebp
  push   %rbx
  lea    D2(%rip),%rbx
  sub    $0x28,%rsp
  mov    %fs:0x28,%rax
  mov    %rax,0x18(%rsp)
  xor    %eax,%eax
  lea    0xc(%rsp),%r12
  jmp    L3
  nopw   0x0(%rax,%rax,1)
L36:
  cmp    $0x1,%eax
  je     L38
  lea    D35(%rip),%rdi
  call   <puts@plt>
  mov    0xc(%rsp),%eax
L69:
  cmp    $0x3,%eax
  je     L22
L3:
  mov    %r15,%rdi
  call   <puts@plt>
  mov    %r14,%rdi
  call   <puts@plt>
  mov    %r13,%rdi
  call   <puts@plt>
  mov    %r12,%rsi
  mov    %rbx,%rdi
  call   <scanf@plt>
  mov    0xc(%rsp),%eax
  cmp    $0x2,%eax
  je     L61
  cmp    $0x3,%eax
  jne    L36
L22:
  mov    0x18(%rsp),%rax
  sub    %fs:0x28,%rax
  jne    L50
  add    $0x28,%rsp
  xor    %eax,%eax
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nopl   0x0(%rax)
L61:
  lea    D19(%rip),%rdi
  call   <puts@plt>
  lea    0x14(%rsp),%rsi
  mov    %rbx,%rdi
  call   <scanf@plt>
  mov    0x14(%rsp),%esi
  mov    %rbp,%rdi
  call   <getNth@plt>
  mov    0x14(%rsp),%esi
  lea    D29(%rip),%rdi
  mov    %eax,0x10(%rsp)
  mov    %eax,%edx
  xor    %eax,%eax
  call   <printf@plt>
  mov    0xc(%rsp),%eax
  jmp    L69
  xchg   %ax,%ax
L38:
  lea    D28(%rip),%rdi
  call   <puts@plt>
  lea    0x10(%rsp),%rsi
  mov    %rbx,%rdi
  call   <scanf@plt>
  mov    0x10(%rsp),%esi
  mov    %rbp,%rdi
  call   <insertAtEnd@plt>
  mov    %rax,%rbp
  mov    0xc(%rsp),%eax
  jmp    L69
L50:
  call   <__stack_chk_fail@plt>
```

tool_calls: name: read_data
arguments: data_tag: D27
type_guessed: string
name: read_data
arguments: data_tag: D32
type_guessed: string
name: read_data
arguments: data_tag: D36
type_guessed: string
name: read_data
arguments: data_tag: D2
type_guessed: string
name: read_data
arguments: data_tag: D35
type_guessed: string
name: read_data
arguments: data_tag: D19
type_guessed: string
name: read_data
arguments: data_tag: D29
type_guessed: string
name: read_data
arguments: data_tag: D28
type_guessed: string

tool: D27: 1. Insert element into a linked list

tool: D32: 2. Find nth element in the linked list

tool: D36: Enter choice

tool: D2: %d

tool: D35: Invalid choice

tool: D19: Enter the value of n

tool: D29: The %dth element in the linked list is %d


tool: D28: Enter the number to be inserted

assistant: ```c
int main(void) {
  struct item *start = NULL;
  int choice, number, n;
  do {
    printf("1. Insert element into a linked list\n");
    printf("2. Find nth element in the linked list\n");
    printf("Enter choice\n");
    scanf("%d", &choice);
    switch (choice) {
    case 1:
      printf("Enter the number to be inserted\n");
      scanf("%d", &number);
      start = insertAtEnd(start, number);
      break;
    case 2:
      printf("Enter the value of n\n");
      scanf("%d", &n);
      number = getNth(start, n);
      printf("The %dth element in the linked list is %d\n", n, number);
      break;
    case 3:
      break;
    default:
      printf("Invalid choice\n");
    }
  } while (choice != 3);
  return 0;
}
```