我认为我唯一的问题是这个未定义的引用......以及我所有的函数调用。我之前做过函数和指针，并尝试遵循相同的格式，但我对自己做错了什么感到迷茫：/我将它们全部作废，定义了我的指针，并给了它们正确的类型......它只是说 4 个错误，说明“未定义对 __menuFunction 的引用”等...
#include<stdio.h>
void menuFunction(float *);
void getDeposit(float *, float *);
void getWithdrawl(float *, float *);
void displayBalance(float );
int main()
{
float menu, deposit,withdrawl, balance;
char selection;
menuFunction (& menu);
getDeposit (&deposit, &balance);
getWithdrawl(&withdrawl, &balance);
displayBalance(balance);
void menuFunction (float *menup)
{
printf("Welcome to HFCC Credit Union!\n");
printf("Please select from the following menu: \n");
printf("D: Make a Deposit\n");
printf("W: Make a withdrawl\n");
printf("B: Check your balance\n");
printf("Or Q to quit\n");
printf("Please make your slelction now: ");
scanf("\n%c", &selection);
}
switch(selection)
{
case'd': case'D':
*getDeposit;
break;
case 'W': case'w':
*getWithdrawl;
break;
case'b': case'B':
*displayBalance;
}
void getDeposit(float *depositp, float *balancep)
{
printf("Please enter how much you would like to deposit: ");
scanf("%f", *depositp);
do
{
*balancep = (*depositp + *balancep);
} while (*depositp < 0);
}
void getWithdrawl(float *withdrawlp, float *balancep)
{
printf("\nPlease enther the amount you wish to withdraw: ");
scanf("%f", *withdrawlp);
do
{
*balancep = (*withdrawlp - *balancep);
} while (*withdrawlp < *balancep);
}
void displayBalance(float balance)
{
printf("\nYour current balance is: %f", balance);
}
return 0;
}