C语言循环和分支。。

#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#define overtime 1.5
#define one_pg 0.15
#define two_pg 0.20
#define three_pg 0.25
char panel(void);
double compensation(double hours,double wage);
int main()
{
    panel();
    printf("Please select an hourly rate\n");
    int a;
    double hours;
    double wage;
    zx:scanf("%d", &a);
    if (a >= 1 && a <=5)
    {
        switch (a)
        {
        case 1 :
        {
            printf("Please enter your working hours\n");
            scanf("%f", &hours);
            wage = 8.75;
            compensation(hours, wage);
            break;
        }
        case 2 :
        {
            printf("Please enter your working hours\n");
            scanf("%f", &hours);
            wage = 9.33;
            compensation(hours, wage);
            break;
        }
        case 3 :
        {
            printf("Please enter your working hours\n");
            scanf("%f", &hours);
            wage = 10.00;
            compensation(hours, wage);
            break;
        }
        case 4 :
        {
            printf("Please enter your working hours\n");
            scanf("%f", &hours);
            wage = 11.20;
            compensation(hours, wage);
            break;
        }
        case 5 :
            printf("Please go to the personnel department to submit your resignation application\n");
            break;
        }
    }
    else
    {
        printf("Please select the correct option\n");
        goto zx;
    }
    return 0;
}
char panel(void)
{
    char s1[] = "(1)$8.75/hr";
    char s2[] = "(2)$9.33/hr";
    char s3[] = "(3)$10.00/hr";
    char s4[] = "(4)$11.20/hr";
    char s5[] = "(5)quit";
    printf("*********************************************\n");
    printf("%-30s", s1);
    printf("%-30s\n", s2);
    printf("%-30s", s3);
    printf("%-30s\n", s4);
    printf("%-30s\n", s5);
    printf("*********************************************\n");
}
double compensation(double hours,double wage)
{
    double PT_salary;
    double AT_salary;
    if (hours <= 40)
    {
        PT_salary = hours * wage;
        if (PT_salary <= 300)
        {
            AT_salary = PT_salary * (1 - one_pg);
            printf("%f\n", AT_salary);
        }
        else if (PT_salary > 300 && PT_salary <= 450);
        {
            AT_salary = 300 * (1 - one_pg) + (PT_salary - 300) * (1 - two_pg);
            printf("%f\n", AT_salary);
        }

    }
    else if (hours > 40)
    {
        hours = 40 + (hours - 40) * overtime;
        PT_salary = hours * wage;
        AT_salary = 300 * (1 - one_pg) + 150 * (1 - two_pg) + (PT_salary - 450) * (1 - three_pg);
        printf("%f\n", AT_salary);
    }
}

//输出结果的时候特别长两串数字
例如：

*********************************************
(1)$8.75/hr                   (2)$9.33/hr
(3)$10.00/hr                  (4)$11.20/hr
(5)quit
*********************************************
Please select an hourly rate
3
Please enter your working hours
45
-786756640795165416242917908014172073586049444062719486342463488.000000
-740476838395449803522746266366279598669223006176677163616436224.000000

scanf("%f", &hours);
改为
scanf("%lf", &hours);
double型输入要用%lf，不能用%f

float是4字节的
double是8字节的
当你输入输出的数据底数和指数都很小的时候，使用%f没问题，4个字节就涵盖了
当你的数据持续增大以后，继续使用%f就会溢出
最好还是改为%lf

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