user: What would the C source look like for the assembly code provided here?

```asm
<scan>:
  endbr64
  sub    $0x8,%rsp
  add    $0x1,%rdi
L45:
  lea    -0x1(%rdi),%rcx
  mov    %rdi,%rdx
  movzbl -0x1(%rdi),%eax
  test   %al,%al
  je     L157
  cmp    $0x3c,%al
  je     L9
L126:
  add    $0x1,%rdi
  jmp    L45
L157:
  mov    $0x0,%esi
  lea    D21(%rip),%rdi
  call   <printf@plt>
  mov    $0x0,%eax
L115:
  add    $0x8,%rsp
  ret
L9:
  movzbl (%rdi),%eax
  cmp    $0x61,%al
  je     L18
  jg     L173
  cmp    $0x41,%al
  je     L18
  sub    $0x42,%eax
  cmp    $0x18,%al
  jbe    L15
  jmp    L126
L173:
  sub    $0x62,%eax
  cmp    $0x18,%al
  ja     L126
  jmp    L15
L18:
  movzbl 0x2(%rcx),%eax
  cmp    $0x5a,%al
  jle    L121
  sub    $0x61,%eax
  cmp    $0x19,%al
  ja     L27
L108:
  lea    0x2(%rcx),%rdx
  jmp    L15
L121:
  cmp    $0x40,%al
  jg     L108
L27:
  mov    $0x1,%esi
  lea    D21(%rip),%rdi
  call   <printf@plt>
  mov    $0x1,%eax
  jmp    L115
L81:
  sub    $0x61,%eax
  cmp    $0x19,%al
  ja     L187
L15:
  add    $0x1,%rdx
  movzbl (%rdx),%eax
  cmp    $0x5a,%al
  jg     L81
  cmp    $0x40,%al
  jg     L15
L187:
  mov    $0x2,%esi
  lea    D21(%rip),%rdi
  call   <printf@plt>
  mov    $0x2,%eax
  jmp    L115
```

tool_calls: name: extract_symbolic_data
arguments: label: D21
type_guessed: string

tool: D21: %d


assistant: ```c
int scan(char *s, int l) {
  char *p = s;
  char *q;
cont : {
  char yych;
  if (((s + l) - p) < 3)
    ;
  yych = *p;
  switch (yych) {
  case 0x00:
    goto yy4;
  case '<':
    goto yy2;
  default:
    goto yy6;
  }
yy2:
  ++p;
  switch ((yych = *p)) {
  case 'A':
  case 'a':
    goto yy7;
  case 'B':
  case 'C':
  case 'D':
  case 'E':
  case 'F':
  case 'G':
  case 'H':
  case 'I':
  case 'J':
  case 'K':
  case 'L':
  case 'M':
  case 'N':
  case 'O':
  case 'P':
  case 'Q':
  case 'R':
  case 'S':
  case 'T':
  case 'U':
  case 'V':
  case 'W':
  case 'X':
  case 'Y':
  case 'Z':
  case 'b':
  case 'c':
  case 'd':
  case 'e':
  case 'f':
  case 'g':
  case 'h':
  case 'i':
  case 'j':
  case 'k':
  case 'l':
  case 'm':
  case 'n':
  case 'o':
  case 'p':
  case 'q':
  case 'r':
  case 's':
  case 't':
  case 'u':
  case 'v':
  case 'w':
  case 'x':
  case 'y':
  case 'z':
    goto yy9;
  default:
    goto yy3;
  }
yy3 : { goto cont; }
yy4:
  ++p;
  {
    printf("%d\n", 0);
    return 0;
  }
yy6:
  yych = *++p;
  goto yy3;
yy7:
  ++p;
  switch ((yych = *p)) {
  case 'A':
  case 'B':
  case 'C':
  case 'D':
  case 'E':
  case 'F':
  case 'G':
  case 'H':
  case 'I':
  case 'J':
  case 'K':
  case 'L':
  case 'M':
  case 'N':
  case 'O':
  case 'P':
  case 'Q':
  case 'R':
  case 'S':
  case 'T':
  case 'U':
  case 'V':
  case 'W':
  case 'X':
  case 'Y':
  case 'Z':
  case 'a':
  case 'b':
  case 'c':
  case 'd':
  case 'e':
  case 'f':
  case 'g':
  case 'h':
  case 'i':
  case 'j':
  case 'k':
  case 'l':
  case 'm':
  case 'n':
  case 'o':
  case 'p':
  case 'q':
  case 'r':
  case 's':
  case 't':
  case 'u':
  case 'v':
  case 'w':
  case 'x':
  case 'y':
  case 'z':
    goto yy9;
  default:
    goto yy8;
  }
yy8 : {
  printf("%d\n", 1);
  return 1;
}
yy9:
  ++p;
  if ((s + l) <= p)
    ;
  yych = *p;
  switch (yych) {
  case 'A':
  case 'B':
  case 'C':
  case 'D':
  case 'E':
  case 'F':
  case 'G':
  case 'H':
  case 'I':
  case 'J':
  case 'K':
  case 'L':
  case 'M':
  case 'N':
  case 'O':
  case 'P':
  case 'Q':
  case 'R':
  case 'S':
  case 'T':
  case 'U':
  case 'V':
  case 'W':
  case 'X':
  case 'Y':
  case 'Z':
  case 'a':
  case 'b':
  case 'c':
  case 'd':
  case 'e':
  case 'f':
  case 'g':
  case 'h':
  case 'i':
  case 'j':
  case 'k':
  case 'l':
  case 'm':
  case 'n':
  case 'o':
  case 'p':
  case 'q':
  case 'r':
  case 's':
  case 't':
  case 'u':
  case 'v':
  case 'w':
  case 'x':
  case 'y':
  case 'z':
    goto yy9;
  default:
    goto yy11;
  }
yy11 : {
  printf("%d\n", 2);
  return 2;
}
}
}
```