为什么它是平衡的0我不明白

Question

#include <iostream>
static float balance = 30000.0;

void deposit(float amount) {
    if (amount < 0.0 && amount > 100000.0 ) {
        printf("Error invalid amount entered ");
    }
    else  {

        balance += amount;
    }

}

float withdrawal(float withdrawal) {

    if (balance == 0.0)
        printf("NO MONEY BROKIE");
    if (withdrawal < 17000.0) {
        printf("Error invalid amount entered ");
    }
    if (balance <= withdrawal) {

        withdrawal = balance;
        balance = 0;
    }

    balance -= withdrawal;
    return withdrawal;

}

void Check() {

    printf("Your Account Balance is : %f ", &balance);
}

int main()
{

    float amount;
    int task;
    printf(" 1. Check Balance \n 2. Deposit \n 3. Withdrawal");
    printf(" \n\nPlease note :\nThe deposit amount must not be greater than $100,000 ");
    printf("\nThe withdrawal amount must not be greater than $17,000  ");
    printf("\n\nWhat service would you like to perform : ");
    scanf_s("%d", &task);

    if (task == 1) {

        Check();
    }
    else if (task == 2) {

        printf("Enter the amount you would like to deposit : ");
        scanf_s("%f", &amount);
            deposit(amount);
        printf("Thanks for doing business you have deposited %f ", &amount );
    }
    else if (task == 3) {

        printf("Enter the amount you would like to withdraw : ");
        scanf_s("%f", &amount);
        float Withdrawal = withdrawal(amount);
        printf("Thanks for doing business you have withdrawn : %f ", &Withdrawal);
    }
    else {
        printf("Invalid task number !");
    }

}

我还以为它能起作用呢。为什么我运行的时候平衡0.0000和任何其他错误，我可能会错过我是新的，所以更多的细节，为什么它要求更详细的.....................................................................................

Answer 1

您犯了一些语法错误，下面是完整的工作代码：

#include <iostream>
static float balance = 30000.0;

void deposit(float amount) {
    if (amount < 0.0 && amount > 100000.0 ) {
        printf("Error invalid amount entered ");
    }
    else  {

        balance += amount;
    }

}

float withdrawal(float withdrawal) {

    if (balance == 0.0)
        printf("NO MONEY BROKIE");
    if (withdrawal < 17000.0) {
        printf("Error invalid amount entered ");
    }
    if (balance <= withdrawal) {

        withdrawal = balance;
        balance = 0;
    }

    balance -= withdrawal;
    return withdrawal;

}

void Check() {

    printf("Your Account Balance is : %f ", balance);
}

int main()
{

    float amount;
    int task;
    printf(" 1. Check Balance \n 2. Deposit \n 3. Withdrawal");
    printf(" \n\nPlease note :\nThe deposit amount must not be greater than $100,000 ");
    printf("\nThe withdrawal amount must not be less than $17,000  ");
    printf("\n\nWhat service would you like to perform : ");
    scanf("%d", &task);

    if (task == 1) {

        Check();
    }
    else if (task == 2) {

        printf("Enter the amount you would like to deposit : ");
        scanf("%f", &amount);
            deposit(amount);
        printf("Thanks for doing business you have deposited %f ", amount );
    }
    else if (task == 3) {

        printf("Enter the amount you would like to withdraw : ");
        scanf("%f", &amount);
        float Withdrawal = withdrawal(amount);
        printf("Thanks for doing business you have withdrawn : %f ", Withdrawal);
    }
    else {
        printf("Invalid task number !");
    }

}

Answer 2

除了字符串外，scanf期望通过指针传递填充的参数。printf期望参数按值传递。

这一行：

printf("Your Account Balance is : %f ", &balance);

应：

printf("Your Account Balance is : %f ", balance);

类似地，还有其他print语句需要通过值而不是指针传递主参数。如这一行：

printf("Thanks for doing business you have withdrawn : %f ", &Withdrawal);

应：

printf("Thanks for doing business you have withdrawn : %f ", Withdrawal);

另一个可能的窃听器。在withdrawl函数中，如果数量小于17000，则代码会打印错误，但不会立即返回。相反，它将继续处理事务。不确定这是否重要。