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

```asm
<main>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x48,%rsp
  mov    %fs:0x28,%rax
  mov    %rax,0x38(%rsp)
  xor    %eax,%eax
  lea    D60(%rip),%rdi
  call   <puts@plt>
  lea    D57(%rip),%r15
  mov    %rsp,%r13
  lea    D33(%rip),%r14
  lea    0x20(%rsp),%r12
L7:
  mov    %r15,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    %r13,%rdi
  call   <gets@plt>
  mov    %r13,%rdi
  call   <string_handler@plt>
  mov    %eax,%ebp
  mov    %r14,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    %r12,%rdi
  call   <gets@plt>
  mov    %r12,%rdi
  call   <string_handler@plt>
  mov    %eax,%ebx
  cmp    $0xffffffff,%eax
  je     L7
  cmp    $0xffffffff,%ebp
  je     L7
  lea    D55(%rip),%rdi
  call   <puts@plt>
  mov    %ebp,%edx
  mov    %ebx,%esi
  lea    D44(%rip),%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  lea    D75(%rip),%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    $0x20,%edx
  mov    $0x0,%esi
  mov    %ebx,%edi
  call   <printbin@plt>
  lea    D82(%rip),%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    $0x20,%edx
  mov    $0x0,%esi
  mov    %ebp,%edi
  call   <printbin@plt>
  lea    D61(%rip),%rdi
  call   <puts@plt>
  mov    %ebx,%esi
  mov    %ebp,%edi
  call   <booth@plt>
  lea    D48(%rip),%rdi
  call   <puts@plt>
  mov    0x38(%rsp),%rax
  sub    %fs:0x28,%rax
  jne    L5
  mov    $0x0,%eax
  add    $0x48,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L5:
  call   <__stack_chk_fail@plt>
```

tool_calls: name: disassemble_data
arguments: label: D60
datatype: string
name: disassemble_data
arguments: label: D57
datatype: string
name: disassemble_data
arguments: label: D33
datatype: string
name: disassemble_data
arguments: label: D55
datatype: string
name: disassemble_data
arguments: label: D44
datatype: string
name: disassemble_data
arguments: label: D75
datatype: string
name: disassemble_data
arguments: label: D82
datatype: string
name: disassemble_data
arguments: label: D61
datatype: string
name: disassemble_data
arguments: label: D48
datatype: string

tool: D60: Start of program:


tool: D57: 
Enter multiplier:   

tool: D33: Enter multiplicand: 

tool: D55: 
================================================================

tool: D44: Multiplying:   %d X %d


tool: D75: Multiplicand: 

tool: D82: 
Multiplier:   

tool: D61: 
=================================================================




tool: D48: 



assistant: ```c
int main() {
  printf("Start of program:\n\n");
  char strMultiplier[20], strMultiplicand[20];
  int multiplier, multiplicand;
  while (1) {
    printf("\nEnter multiplier:   ");
    gets(strMultiplier);
    multiplier = string_handler(strMultiplier);
    printf("Enter multiplicand: ");
    gets(strMultiplicand);
    multiplicand = string_handler(strMultiplicand);
    if (multiplicand != -1 && multiplier != -1)
      break;
  }
  printf("\n================================================================\n");
  printf("Multiplying:   %d X %d\n", multiplicand, multiplier);
  printf("Multiplicand: ");
  printbin(multiplicand, 0, 32);
  printf("\nMultiplier:   ");
  printbin(multiplier, 0, 32);
  printf("\n=================================================================\n\n\n\n");
  booth(multiplier, multiplicand);
  printf("\n\n\n");
  return 0;
}
```