user: What is the c source code of the assembly code below?

```asm
<longest_path_recursion>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x50,%rsp
  mov    %rdi,-0x28(%rbp)
  mov    %rsi,-0x30(%rbp)
  mov    %rdx,-0x38(%rbp)
  mov    %ecx,-0x3c(%rbp)
  mov    %r8d,-0x40(%rbp)
  mov    %r9d,-0x44(%rbp)
  mov    -0x40(%rbp),%eax
  cmp    -0x44(%rbp),%eax
  jne    L36
  movl   $0x0,-0x14(%rbp)
  mov    -0x44(%rbp),%eax
  mov    %eax,-0x10(%rbp)
  jmp    L30
L9:
  mov    -0x10(%rbp),%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%rdx
  mov    -0x10(%rbp),%eax
  cltq
  shl    $0x2,%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  add    %eax,-0x14(%rbp)
  mov    -0x10(%rbp),%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  mov    %eax,-0x10(%rbp)
L30:
  mov    -0x10(%rbp),%eax
  cmp    0x10(%rbp),%eax
  jne    L9
  mov    -0x14(%rbp),%eax
  jmp    L79
L36:
  movl   $0xffffffff,-0xc(%rbp)
  movl   $0xffffffff,-0x4(%rbp)
  movl   $0x0,-0x8(%rbp)
  jmp    L44
L29:
  mov    -0x8(%rbp),%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x30(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  test   %eax,%eax
  jne    L72
  mov    -0x40(%rbp),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%rdx
  mov    -0x8(%rbp),%eax
  cltq
  shl    $0x2,%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  test   %eax,%eax
  jle    L72
  mov    -0x8(%rbp),%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x30(%rbp),%rax
  add    %rdx,%rax
  movl   $0x1,(%rax)
  mov    -0x8(%rbp),%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rax,%rdx
  mov    -0x40(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x44(%rbp),%r9d
  mov    -0x8(%rbp),%r8d
  mov    -0x3c(%rbp),%ecx
  mov    -0x38(%rbp),%rdx
  mov    -0x30(%rbp),%rsi
  mov    -0x28(%rbp),%rax
  sub    $0x8,%rsp
  mov    0x10(%rbp),%edi
  push   %rdi
  mov    %rax,%rdi
  call   <longest_path_recursion>
  add    $0x10,%rsp
  mov    %eax,-0x4(%rbp)
  mov    -0x4(%rbp),%eax
  cmp    -0xc(%rbp),%eax
  jle    L59
  mov    -0x4(%rbp),%eax
  mov    %eax,-0xc(%rbp)
L59:
  mov    -0x8(%rbp),%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x30(%rbp),%rax
  add    %rdx,%rax
  movl   $0x0,(%rax)
L72:
  addl   $0x1,-0x8(%rbp)
L44:
  mov    -0x8(%rbp),%eax
  cmp    -0x3c(%rbp),%eax
  jl     L29
  mov    -0xc(%rbp),%eax
L79:
  leave
  ret
```

assistant: ```c
int longest_path_recursion(int **graph, int *visited, int *pred, int n, int s, int t, int source) {
  if (s == t) {
    int cost = 0, vertex = t, i;
    while (vertex != source) {
      cost += graph[pred[vertex]][vertex];
      vertex = pred[vertex];
    }
    return cost;
  }
  int max = -1, maybeMax = -1, i;
  for (i = 0; i < n; i++) {
    if (visited[i] == 0 && graph[s][i] > 0) {
      visited[i] = 1;
      pred[i] = s;
      maybeMax = longest_path_recursion(graph, visited, pred, n, i, t, source);
      if (maybeMax > max) {
        max = maybeMax;
      }
      visited[i] = 0;
    }
  }
  return max;
}
```