C primer plus 编程练习 5.11

1.

#include <stdio.h>
#define MIN_PER_HOUR 60
int main(void)
{
	int mins,hour,min;

	printf("Please input the number of minutes to convert: ");
	scanf("%d",&mins);
	while (mins > 0)
	{
		hour = mins / MIN_PER_HOUR;
		min = mins % MIN_PER_HOUR;
		printf("%d mins = %d hours, %d mins\n",mins,hour,min);
		printf("Please input the next minutes value(<= 0 to quit): ");
		scanf("%d",&mins);
	}
	printf("GAME OVER");

	return 0;
}

---

2.

#include <stdio.h>

int main(void)
{
	int num,numend;

	printf("enter a number:");
	scanf("%d",&num);
	numend = num + 10;
	num--;
	while (num++ < numend)
		printf("%d\t",num);

	return 0;
}

---

3.

#include <stdio.h>
#define DAYS_PER_WEEK 7;

int main(void)
{
	int days,week,day;

	printf("enter a number of days: ");
	scanf("%d",&days);
	
	while (days > 0)
	{
		day = days % 7;
		week = days / 7;
		printf("%d days = %d weeks and %d days\n",days,week,day);
		printf("enter a number of days(<= 0 to quit): ");
		scanf("%d",&days);
	}
    printf("over");

	return 0;
}

---

4.

#include <stdio.h>

int main(void)
{
	const float CM_PER_FOOT = 30.38;
	const float CM_PER_INCHE = 2.54;
	float cm,inches;
	int feet;

	printf("enter a height in centimeters: ");
	scanf("%f",&cm);

	while (cm > 0)
	{
		feet = cm / CM_PER_FOOT;
		inches = (cm - feet * CM_PER_FOOT) / CM_PER_INCHE;
		printf("%.1fcm = %dfeet, %.1finches\n",cm,feet,inches);
        printf("enter a height in centimeters(<=0 to quit): ");
		scanf("%f",&cm);
	}
	printf("bye");

	return 0;
}

---

5.

#include <stdio.h>

int main(void)
{
	int count,sum;
	int n;

	printf("Enter the upper limit: ");
	scanf("%d",&n);
	count = 0;
	sum = 0;

	while (count++ < n)
		sum = sum + count;
	printf("sum = %d\n",sum);

	return 0;
}

---

6.

#include <stdio.h>

int main(void)
{
	int count,sum;
	int n;

	printf("Enter the upper limit: ");
	scanf("%d",&n);
	count = 0;
	sum = 0;

	while (count++ < n)
		sum = sum + count * count;
	printf("sum = %d\n",sum);

	return 0;
}

---

7.

#include <stdio.h>
void cube(double c);

int main(void)
{
	double num;
	printf("Enter a number: ");
	scanf("%lf",&num);
	cube(num);

	return 0;
}
void cube(double c)
{
	printf("The cube of %e is %e.\n",c,c*c*c);
}

---

8.

#include <stdio.h>

int main(void)
{
	int operand1,operand2;

	printf("This program computes moduli\n");
	printf("Enter an integer to serve as the second operand: ");
	scanf("%d",&operand2);
	printf("Now enter the first operand: ");
	scanf("%d",&operand1);

	while (operand1 > 0)
	{
		printf("%d %% %d is %d\n",operand1,operand2,operand1 % operand2);
		printf("Enter next number for first operand (<= 0 to quit): ");
	    scanf("%d",&operand1);
	}
	printf("done!");

	return 0;
}

---

9.

#include <stdio.h>
void temperatures(double a);

int main(void)
{
	int n;
	double tem_f;
	printf("enter a value of  Fahrenheit: ");
	n = scanf("%lf",&tem_f);

	while (n == 1)
	{
	    temperatures(tem_f);
		printf("enter the next value of  Fahrenheit: ");
	    n = scanf("%lf",&tem_f);
	}
	printf("done!");

	return 0;
}
void temperatures(double a)
{
	double tem_c,tem_k;
	const double con1 = 5.0,con2 = 9.0,con3 = 32.0,con4 = 273.16;

	tem_c = con1 / con2 * (a - con3);
	tem_k = tem_c + con4;
	printf("华氏温度=%0.2f\n摄氏温度=%0.2f%\n开氏温度=%0.2f\n",a,tem_c,tem_k);
}