我想调用一个函数来填充C中的一个结构的值。我有以下代码，但出现类似[Error] request for member 'id' in something not a structure or union的错误。
#include <stdio.h>
typedef struct {
int id;
float grades[3];
} student_t;
void scan_student (student_t *s) {
printf("Please give student's info:\n");
scanf("%d%f%f%f", s.id, s.grades[0], s.grades[1], s.grades[2]);
}
int main ()
{
student_t stu2;
scan_student(&stu2);
printf("Student's info are:\n");
printf("%6d %5.2f %5.2f %5.2f\n", stu2.id, stu2.grades[0], stu2.grades[1], stu2.grades[2]);
return 0;
}
答案 0 :(得分：9)
Sub CrossSumSolver()
Dim StartTime As Double
Dim SecondsElapsed As Double
StartTime = Timer
Dim wb As Workbook
Dim ws As Worksheet
Set wb = ThisWorkbook
Set ws = wb.Worksheets("Sheet1")
Application.Calculation = xlCalculationManual
Application.ScreenUpdating = False
Dim OutputArray(1 To 9) As Long, IsValid As Boolean, CheckLoop As Long
Dim a&, b&, c&, d&, e&, f&, g&, h&, i& 'All "As Long"
For a = 1 To 9
OutputArray(1) = a
For b = 1 To 9
OutputArray(2) = b
For c = 1 To 9
OutputArray(3) = c
For d = 1 To 9
OutputArray(4) = d
For e = 1 To 9
OutputArray(5) = e
For f = 1 To 9
OutputArray(6) = f
For g = 1 To 9
OutputArray(7) = g
For h = 1 To 9
OutputArray(8) = h
For i = 1 To 9
OutputArray(9) = i
'Array is populated - is it valid?
IsValid = True
'Are all 9 numbers used once?
For CheckLoop = 1 To 9
If IsError(Application.Match(CheckLoop, OutputArray, 0)) Then
IsValid = False 'A number is missing!
Exit For 'Only need to find 1 error
End If
Next CheckLoop
If IsValid Then
'Populate sheet
ws.Range("A1").Value = OutputArray(1)
ws.Range("C1").Value = OutputArray(2)
ws.Range("E1").Value = OutputArray(3)
ws.Range("A3").Value = OutputArray(4)
ws.Range("C3").Value = OutputArray(5)
ws.Range("E3").Value = OutputArray(6)
ws.Range("A5").Value = OutputArray(7)
ws.Range("C5").Value = OutputArray(8)
ws.Range("E5").Value = OutputArray(9)
'Calculate sheet
ws.Calculate
'Check if your output is correct
If (False) Then GoTo QuickExit 'Replace (False) with your check!
End If
Next i, h, g, f, e, d, c, b, a 'No need for a Wall of "Next"
QuickExit:
Application.Calculation = xlCalculationAutomatic
Application.ScreenUpdating = True
SecondsElapsed = Round(Timer - StartTime, 2)
MsgBox "This code ran successfully in " & SecondsElapsed & " seconds", vbInformation
End Sub
是指针，而不是结构。这意味着您不能在其上使用Option Explicit
Private ValueArray(1 To 9) As Long
Private wb As Workbook
Private ws As Worksheet
Public Sub ControlLoop()
Dim StartTime As Double
Dim SecondsElapsed As Double
StartTime = Timer
Set wb = ThisWorkbook
Set ws = wb.Worksheets("Sheet1")
Application.Calculation = xlCalculationManual
Application.ScreenUpdating = False
Dim OutermostLoop As Long
For OutermostLoop = 1 To 9
ClearArrayAbove 1
RecursiveArrayLoop 1, OutermostLoop
Next OutermostLoop
Application.Calculation = xlCalculationAutomatic
Application.ScreenUpdating = True
SecondsElapsed = Round(Timer - StartTime, 2)
MsgBox "This code ran successfully in " & SecondsElapsed & " seconds", vbInformation
End Sub
Private Sub ClearArrayAbove(ArrayItem As Long)
If ArrayItem >= 9 Then Exit Sub 'Safety check
Dim InnerLoop As Long
For InnerLoop = ArrayItem To 9
ValueArray(InnerLoop) = 0
Next InnerLoop
End Sub
Private Sub RecursiveArrayLoop(ArrayItem As Long, NewValue As Long)
Dim InnerLoop As Long
'Number is not already in the array
If IsError(Application.Match(NewValue, ValueArray, 0)) Then
'Add number to array
ValueArray(ArrayItem) = NewValue
If ArrayItem < 9 Then
'Go up a level, and loop again
For InnerLoop = 1 To 9
ClearArrayAbove ArrayItem
RecursiveArrayLoop ArrayItem + 1, InnerLoop
Next InnerLoop
Else
'All numbers filled!
TestValidNumbers
End If
End If
End Sub
Private Sub TestValidNumbers()
'Populate sheet
ws.Range("A1").Value = ValueArray(1)
ws.Range("C1").Value = ValueArray(2)
ws.Range("E1").Value = ValueArray(3)
ws.Range("A3").Value = ValueArray(4)
ws.Range("C3").Value = ValueArray(5)
ws.Range("E3").Value = ValueArray(6)
ws.Range("A5").Value = ValueArray(7)
ws.Range("C5").Value = ValueArray(8)
ws.Range("E5").Value = ValueArray(9)
'Calculate sheet
ws.Calculate
'Check if your output is correct
'Do stuff here?
End Sub
。
相反，您必须编写s（先引用，然后访问结构成员）或.（相同，但更短）。
此外，(*s).id s->id需要一个指针，因此应该是scanf，等等。
答案 1 :(得分：0)
我还发布了一个不使用指针的示例：
#include <stdio.h>
typedef struct {
int id;
float grades[3];
} student_t;
student_t scan_student () {
student_t s;
printf("Please give patient's info:\n");
scanf("%d%f%f%f", &s.id, &s.grades[0], &s.grades[1], &s.grades[2]);
return s;
}
int main ()
{
student_t stu2;
stu2= scan_student();
printf("Student's info are:\n");
printf("%6d %5.2f %5.2f %5.2f\n", stu2.id, stu2.grades[0], stu2.grades[1], stu2.grades[2]);
return 0;
}