user: 这段汇编代码用C语言表示是什么样的:

```asm
<strtoul>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  mov    %rdi,-0x18(%rbp)
  mov    %rsi,-0x20(%rbp)
  mov    -0x20(%rbp),%rax
  movq   $0x0,(%rax)
  mov    -0x18(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x30,%al
  jne    L1
  mov    -0x18(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%eax
  cmp    $0x78,%al
  je     L164
L1:
  mov    -0x18(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x30,%al
  jne    L288
  mov    -0x18(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%eax
  cmp    $0x58,%al
  jne    L288
L164:
  movq   $0x10,-0x8(%rbp)
  movq   $0x2,-0x10(%rbp)
  jmp    L82
L288:
  mov    -0x18(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x30,%al
  jne    L302
  mov    -0x18(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%eax
  cmp    $0x62,%al
  je     L8
L302:
  mov    -0x18(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x30,%al
  jne    L51
  mov    -0x18(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%eax
  cmp    $0x42,%al
  jne    L51
L8:
  movq   $0x2,-0x8(%rbp)
  movq   $0x2,-0x10(%rbp)
  jmp    L82
L51:
  movq   $0xa,-0x8(%rbp)
  movq   $0x0,-0x10(%rbp)
L82:
  jmp    L173
L308:
  cmpq   $0x2,-0x8(%rbp)
  jne    L45
  mov    -0x18(%rbp),%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x2f,%al
  jle    L87
  mov    -0x18(%rbp),%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x31,%al
  jg     L87
L45:
  cmpq   $0xa,-0x8(%rbp)
  jne    L221
  mov    -0x18(%rbp),%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x2f,%al
  jle    L87
  mov    -0x18(%rbp),%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x39,%al
  jg     L87
L221:
  cmpq   $0x10,-0x8(%rbp)
  jne    L159
  mov    -0x18(%rbp),%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x2f,%al
  jle    L203
  mov    -0x18(%rbp),%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x39,%al
  jle    L159
L203:
  mov    -0x18(%rbp),%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x60,%al
  jle    L172
  mov    -0x18(%rbp),%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x66,%al
  jle    L159
L172:
  mov    -0x18(%rbp),%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x40,%al
  jle    L87
  mov    -0x18(%rbp),%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x46,%al
  jg     L87
L159:
  mov    -0x20(%rbp),%rax
  mov    (%rax),%rax
  imul   -0x8(%rbp),%rax
  mov    %rax,%rdx
  mov    -0x20(%rbp),%rax
  mov    %rdx,(%rax)
  mov    -0x18(%rbp),%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x39,%al
  jg     L95
  mov    -0x20(%rbp),%rax
  mov    (%rax),%rdx
  mov    -0x18(%rbp),%rcx
  mov    -0x10(%rbp),%rax
  add    %rcx,%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  sub    $0x30,%eax
  cltq
  add    %rax,%rdx
  mov    -0x20(%rbp),%rax
  mov    %rdx,(%rax)
  jmp    L77
L95:
  mov    -0x18(%rbp),%rdx
  mov    -0x10(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x5a,%al
  jg     L298
  mov    -0x20(%rbp),%rax
  mov    (%rax),%rdx
  mov    -0x18(%rbp),%rcx
  mov    -0x10(%rbp),%rax
  add    %rcx,%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  sub    $0x37,%eax
  cltq
  add    %rax,%rdx
  mov    -0x20(%rbp),%rax
  mov    %rdx,(%rax)
  jmp    L77
L298:
  mov    -0x20(%rbp),%rax
  mov    (%rax),%rdx
  mov    -0x18(%rbp),%rcx
  mov    -0x10(%rbp),%rax
  add    %rcx,%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  sub    $0x57,%eax
  cltq
  add    %rax,%rdx
  mov    -0x20(%rbp),%rax
  mov    %rdx,(%rax)
L77:
  addq   $0x1,-0x10(%rbp)
L173:
  cmpq   $0xf,-0x10(%rbp)
  jbe    L308
L87:
  cmpq   $0x0,-0x10(%rbp)
  jne    L165
  mov    $0x0,%eax
  jmp    L132
L165:
  mov    $0x1,%eax
L132:
  pop    %rbp
  ret
```

assistant: ```c
int strtoul(const char *number, unsigned long *result) {
  unsigned long n, n_num, weight;
  *result = 0;
  if (((number[0] == '0') && (number[1] == 'x')) || ((number[0] == '0') && (number[1] == 'X'))) {
    weight = 16;
    n = 2;
  } else if (((number[0] == '0') && (number[1] == 'b')) || ((number[0] == '0') && (number[1] == 'B'))) {
    weight = 2;
    n = 2;
  } else {
    weight = 10;
    n = 0;
  }
  for (; n < 16; n++) {
    if ((weight == 02) && ((number[n] < '0') || (number[n] > '1')))
      break;
    if ((weight == 10) && ((number[n] < '0') || (number[n] > '9')))
      break;
    if ((weight == 16) && ((number[n] < '0') || (number[n] > '9')) && ((number[n] < 'a') || (number[n] > 'f')) && ((number[n] < 'A') || (number[n] > 'F')))
      break;
    *result = *result * weight;
    if (number[n] <= '9') {
      *result = *result + (number[n] - '0');
    } else if (number[n] <= 'Z') {
      *result = *result + (number[n] - 'A' + 10);
    } else {
      *result = *result + (number[n] - 'a' + 10);
    }
  }
  if (n == 0)
    return 0;
  return 1;
}
```