user: 请从给定的汇编指令推导出C源代码：

```asm
<main>:
  endbr64
  push   %r15
  lea    D74(%rip),%rdi
  lea    D139(%rip),%r15
  push   %r14
  push   %r13
  lea    D28(%rip),%r13
  push   %r12
  push   %rbp
  push   %rbx
  lea    D62(%rip),%rbx
  sub    $0x38,%rsp
  mov    %fs:0x28,%rax
  mov    %rax,0x28(%rsp)
  xor    %eax,%eax
  mov    D20(%rip),%rax
  lea    0x14(%rsp),%r14
  mov    %rax,0x18(%rsp)
  call   <puts@plt>
  jmp    L49
  cs nopw 0x0(%rax,%rax,1)
L41:
  lea    D65(%rip),%rdi
  call   <puts@plt>
L10:
  cmpl   $0x3,0x14(%rsp)
  je     L16
L49:
  movsd  0x18(%rsp),%xmm0
  mov    %r13,%rdi
  mov    $0x1,%eax
  call   <printf@plt>
  lea    D117(%rip),%rdi
  xor    %eax,%eax
  call   <printf@plt>
  lea    D102(%rip),%rdi
  call   <puts@plt>
  lea    D23(%rip),%rdi
  xor    %eax,%eax
  call   <printf@plt>
  mov    %r14,%rsi
  mov    %r15,%rdi
  xor    %eax,%eax
  call   <scanf@plt>
  mov    $0xa,%edi
  call   <putchar@plt>
  mov    0x14(%rsp),%eax
  cmp    $0x1,%eax
  je     L50
  cmp    $0x2,%eax
  je     L36
  cmp    $0x3,%eax
  jne    L41
  lea    D54(%rip),%rdi
  call   <puts@plt>
  cmpl   $0x3,0x14(%rsp)
  jne    L49
L16:
  mov    0x28(%rsp),%rax
  sub    %fs:0x28,%rax
  jne    L84
  add    $0x38,%rsp
  xor    %eax,%eax
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L50:
  lea    D15(%rip),%rdi
  xor    %eax,%eax
  call   <printf@plt>
  lea    0x18(%rsp),%rsi
  mov    %rbx,%rdi
  xor    %eax,%eax
  call   <scanf@plt>
  jmp    L10
  nopw   0x0(%rax,%rax,1)
L36:
  movq   $0x0,0x8(%rsp)
  lea    D2(%rip),%r12
  lea    0x20(%rsp),%rbp
  nopl   (%rax)
L42:
  mov    %r12,%rdi
  xor    %eax,%eax
  call   <printf@plt>
  xor    %eax,%eax
  mov    %rbp,%rsi
  mov    %rbx,%rdi
  call   <scanf@plt>
  movsd  0x20(%rsp),%xmm0
  pxor   %xmm1,%xmm1
  comisd %xmm1,%xmm0
  jb     L92
  addsd  0x8(%rsp),%xmm0
  movsd  %xmm0,0x8(%rsp)
  jmp    L42
  nopl   (%rax)
L92:
  movsd  0x8(%rsp),%xmm0
  lea    D75(%rip),%rdi
  mov    $0x1,%eax
  call   <printf@plt>
  movsd  0x8(%rsp),%xmm0
  mulsd  0x18(%rsp),%xmm0
  lea    D91(%rip),%rdi
  mov    $0x1,%eax
  call   <printf@plt>
  movsd  0x20(%rsp),%xmm0
  pxor   %xmm3,%xmm3
  comisd %xmm3,%xmm0
  jae    L42
  jmp    L10
L84:
  call   <__stack_chk_fail@plt>
```

tool_calls: name: disassemble_data
arguments: data_label: D74
type: string
name: disassemble_data
arguments: data_label: D139
type: string
name: disassemble_data
arguments: data_label: D28
type: string
name: disassemble_data
arguments: data_label: D62
type: string
name: disassemble_data
arguments: data_label: D20
type: f64
name: disassemble_data
arguments: data_label: D65
type: string
name: disassemble_data
arguments: data_label: D117
type: string
name: disassemble_data
arguments: data_label: D102
type: string
name: disassemble_data
arguments: data_label: D23
type: string
name: disassemble_data
arguments: data_label: D54
type: string
name: disassemble_data
arguments: data_label: D15
type: string
name: disassemble_data
arguments: data_label: D2
type: string
name: disassemble_data
arguments: data_label: D75
type: string
name: disassemble_data
arguments: data_label: D91
type: string

tool: D74: Your shopping assistant

tool: D139: %d

tool: D28: 
1. Set exchange rate in SEK (current rate: %.2f)

tool: D62: %lf

tool: D20: 1

tool: D65: Not a valid choice!

tool: D117: 
2. Read prices in the foreign currency

tool: D102: 
3. End

tool: D23: 
Give your choice (1 - 3): 

tool: D54: End of program!


tool: D15: Give exchange rate: 

tool: D2: Give price (finish with < 0): 

tool: D75: 
Sum in foreign currency: %.2f

tool: D91: 
Sum in SEK: %.2f


assistant: ```c
int main() {
  int menuSelection;
  double currencyRate = 1.0;
  printf("Your shopping assistant\n");
  do {
    printf("\n1. Set exchange rate in SEK (current rate: %.2f)", currencyRate);
    printf("\n2. Read prices in the foreign currency");
    printf("\n3. End\n");
    printf("\nGive your choice (1 - 3): ");
    scanf("%d", &menuSelection);
    printf("\n");
    if (menuSelection == 1) {
      printf("Give exchange rate: ");
      scanf("%lf", &currencyRate);
    } else if (menuSelection == 2) {
      double priceSum = 0;
      double price;
      do {
        printf("Give price (finish with < 0): ");
        scanf("%lf", &price);
        if (price >= 0) {
          priceSum = priceSum + price;
        } else {
          printf("\nSum in foreign currency: %.2f", priceSum);
          printf("\nSum in SEK: %.2f\n", (priceSum * currencyRate));
        }
      } while (price >= 0);
    } else if (menuSelection == 3) {
      printf("End of program!\n\n");
    } else {
      printf("Not a valid choice!\n");
    }
  } while (menuSelection != 3);
}
```