C Prime Plus (第6版) 第五章 练习题

5.11的习题答案，自己写的：）
环境： Windows、Dev-C++ 5.11、TDM-GCC 4.9.2。

1.

//5.11.1
#include  
#define SIXTY 60

int main(void)
{
    int minute;

    printf("请输入分钟数,按0退出：\n");
    while((scanf("%d",&minute) == 1) && minute > 0)
    {
        getchar() ;
        printf("您输入的是%d分钟,",minute);
        printf("转换后是 %d 小时 %.1d 分钟。\n",minute/SIXTY, minute%SIXTY);
        printf("\n请输入分钟数,按0退出：\n");
    }
    printf("谢谢使用：）");
    getchar();

    return 0;
}

2.

//5.11.2 
#include  

int main(void)
{
    int in_value,temp;

    printf("请输入一个整数:\n");
    scanf("%d",&in_value);
    temp = in_value+10;
    while(in_value <= temp)
        printf("%d ",in_value++);

    return 0;
}

3.

//5.11.3
#include 

int main(void)
{
    int days;

    printf("Please enter days(0 to quit)：\n");
    while((scanf("%d",&days) == 1) && days > 0)
    {
        getchar();
        printf("%d days are %d weeks, %d days.\n",days,days/7,days%7);
        printf("\nPlease input days(enter 0 exit)：\n");
    }
    printf("Thanks you for using:)");
    getchar() ;

    return 0;
}

4.

//5.11.4
//in = ft*12 = cm*0.3937
#include 

int main(void)
{
    float height;

    printf("Enter a height in centimeters:");
    while((scanf("%f",&height) == 1) && height > 0)
    {
        getchar();
        printf("%.1f cm = %d feet, %.1f inches\n",height,(int)(height*0.3937/12),((height*0.3937/12)-(int)(height*0.3937/12))*12);
        printf("Enter a height in centimeters (<=0 to quit):");
    }
    printf("bye");
    getchar();

    return 0;
}
//上面那一长溜的printf应该不好，应该多定义个变量，比如ft_height,开始的height改为cm_height。

5.

//5.11.5
/* addemup.c -- five kinds of statements */

#include 
int main(void)                /* finds sum of first 20 integers */
{
    int count, sum;           /* declaration statement          */
    int days;

    printf("Please enter working days:");
    scanf("%d",&days);
    getchar();
    count = 0;                /* assignment statement           */
    sum = 0;                  /* ditto                          */
    while (count++ < days)      /* while                          */
        sum = sum + count;    /*     statement                  */
    printf("sum = %d\n", sum);/* function statement             */

    return 0;                 /* return statement               */
}
//这里就是在复制粘贴原文的基础上稍稍改动：）

6.

//5.11.6
/* addemup.c -- five kinds of statements */

#include 
int main(void)                /* finds sum of first 20 integers */
{
    int count, sum;           /* declaration statement          */
    int days;

    printf("Please enter working days:");
    scanf("%d",&days);
    getchar();
    count = 0;                /* assignment statement           */
    sum = 0;                  /* ditto                          */
    while (count++ < days)      /* while                          */
        sum = sum + count*count;    /*     statement                  */
    printf("sum = %d\n", sum);/* function statement             */

    return 0;                 /* return statement               */
}

7.

//5.11.7
#include  
void cubic_value(double);

int main(void)
{
    double input;

    printf("请输入一个双精度浮点值：\n");
    scanf("%lf",&input);
    cubic_value(input);

    return 0;
}

void cubic_value(double x)
{
    printf("该数的立方值是%.2lf.",x*x*x);
}

8.

//5.11.8
#include 

int main(void)
{
    int f_operand,s_operand;

    printf("This program computs moduli.\n");
    printf("Enter an integer to serve as the second operand:");
    scanf("%d",&s_operand);
    printf("Now enter the first operand:");
    while((scanf("%d",&f_operand) == 1) && f_operand >0 )
    {
        printf("%d %% %d is %d\n",f_operand,s_operand,f_operand%s_operand);
        printf("Enter next number for first operand(<=0 to quit):");
    }
    printf("Done");

    return 0;
}

9.

//5.11.9
#include 
void Temperatures(double);

int main(void)
{
    double f_temp;

    printf("请输入温度（华氏度）(q退出)：");
    while((scanf("%lf",&f_temp) == 1) )
    {
        getchar();
        Temperatures(f_temp);
        printf("\n请输入温度（华氏度）(q退出)：");
    }
    printf("再见"); 

    return 0;
}

void Temperatures(double f_temp)
{
    const float k_to_s = 273.16;
    const float s_to_f = 32.0;
    double c_temp = 5.0/9.0*(f_temp - s_to_f);

    printf("输入的 %.2lf 华氏度，是 %.2lf 摄氏度，是 %.2lf 开氏度\n",f_temp,c_temp,c_temp+k_to_s);
}