C primer plus(第六版）第四章源代码

第四章

/*   4.1    */
#include<stdio.h>
#include<string.h>
#define DENSITY 62.4;
int main(void)
{
	float weight,volume;
	int size, letters;
	char name[40];
	
	printf("Hi! What's your first name?\n");
	scanf("%s",name);
	printf("%s , what's your weight in pounds?\n",name);
	scanf("%f",&weight);
	size = sizeof name;
	letters = strlen(name);
	volume = weight / DENSITY;
	printf("Well, %s ,your volume is %2.2f cubic feet.\n",name,volume);
	printf("Also, your first name has %d letters,\n",letters);
	printf("and we have %d bytes to store it.\n",size);
	
	return 0;
	
}  

/*  4.2    */
#include<stdio.h>
#define PRAISE "You are an extraordinary being."
int main(void)
{
	char name[40];
	
	printf("What's your name?");
	scanf("%s",name);
	printf("Hello, %s. %s\n",name , PRAISE);
	
	return 0;
}   

/*    4.3    */
#include<stdio.h>
#include<string.h>
#define PRAISE "You are an extraordinary being."
int main(void)
{
	char name[40];
	
	printf("What's your name?");
	scanf("%s",name);
	printf("Hello, %s. %s\n",name , PRAISE);
	printf("Your name of %zd letters occupies %zd memory cells.\n",strlen(name),sizeof(name));
	printf("The phrase of praise has %zd letters",strlen(PRAISE));
	printf("and occupies %zd memory cells.\n",sizeof(PRAISE));
	
	return 0;
	return 0;
}      

/*     4.4   */
#include<stdio.h>
#define PI 3.14159
int main(void)
{
	float area, circum, radius;
	
	printf("What is the radius of your pizza?\n");
	scanf("%f",&radius);
	area = PI * radius * radius;
	circum = 2.0 * PI *radius;
	printf("Your basic pizza parameters are as follows:\n");
	printf("circumference = %1.2f,area = %1.2f\n",circum,area);
	
	return 0;
}     

/*     4.5   */
#include<stdio.h>
#include<limits.h>
#include<float.h>
int main(void)
{
	printf("Some nember limits for this system:\n");
	printf("Biggest int: %d\n",INT_MAX);
	printf("Smallest long long: %lld\n",LLONG_MIN);
	printf("One byte = %d bits on this system.\n",CHAR_BIT);
	printf("Largest double: %e\n",DBL_MAX);
	printf("Smallest normal float: %e\n",FLT_MIN);
	printf("float precision = %d digits\n",FLT_DIG);
	printf("float epsilon = %e\n",FLT_EPSILON);
	
	return 0;
}    

/*    4.6   */
#include<stdio.h>
#define PI 3.141593
int main(void)
{
	int number = 7;
	float pies = 12.75;
	int cost = 7800;
	
	printf("The %d contestants ate %f berry pies.\n",number,pies);
	printf("The value of pi is %f.\n",PI);
	printf("Farewell! thou art too dear for my possessing,\n");
	printf("%c%d\n",'$',2 * cost);
	
	return 0;
}     

/*  4.7    */
#include<stdio.h>
#define PAGES 959
int main(void)
{
	printf("*%d*\n",PAGES);
	printf("*%2d*\n",PAGES);
	printf("*%10d*\n",PAGES);
	printf("*%-10d*\n",PAGES);
	
	return 0;
}     

/*     4.8   */
#include<stdio.h>
int main(void)
{
	const double RENT = 3852.99;
	
	printf("*%f*\n",RENT);
	printf("*%e*\n",RENT);
	printf("%4.2f*\n",RENT);
	printf("*%3.1f*\n",RENT);
	printf("*%10.3f*\n",RENT);
	printf("*%10.3e*\n",RENT);
	printf("*%+4.2f*\n",RENT);
	printf("*%010.2f*\n",RENT);
	
	return 0;
}      

/*    4.9   */
#include<stdio.h>
int main(void)
{
	printf("%x %X %#x\n",31,31,31);
	printf("**%d**% d**% d**\n",42,42,-42);
	printf("**%5d**%5.3d**%05d**%05.3d**\n",6,6,6,6);
	
	return 0;
}      

/*   4.10  */
#include<stdio.h>
#define BLURB "Authentic imitation!"
int main(void)
{
	printf("[%2s]\n",BLURB);
	printf("[%24s]\n",BLURB);
	printf("[%24.5s]\n",BLURB);    //.5告诉printf（）只打印5个字符 
	printf("[%-24.5s]\n",BLURB);
	
	return 0;
}    

/*     4.11  */
#include<stdio.h>
#define PAGES 336
#define WORDS 65618
int main(void)
{
	short num = PAGES;
	short munm = -PAGES;
	
	printf("num as short and unsigned short: %hd %hu\n",num,num);
	printf("-num as short and unsigned short: %hd %hu\n",munm,munm);
	printf("num as int and char: %d %c\n",num,num);
	printf("WORDS as int ,short, and char: %d %hd %c\n",WORDS,WORDS,WORDS);
	
	return 0;
}     

/*   4.12   */
#include<stdio.h>
int main(void)
{
	float n1 = 3.0;
	double n2 = 3.0;
	long n3 = 2000000000;
	long n4 = 1234567890;
	
	printf("%.1e %.1e %.1e %.1e\n",n1,n2,n3,n4);
	printf("%ld %ld\n",n3,n4);
	printf("%ld %ld %ld %ld",n1,n2,n3,n4);
	
	return 0;
}    

/*   4.13   */
#include<stdio.h>
int main(void)
{
	int bph2o = 212;
	int rv;
	
	rv = printf("%d F is water's boiling point.\n",bph2o);  //此语句将printf()的返回值赋给rv 
	printf("The printf() function printed %d characters.\n",rv);
	
	return 0;
}      

/*   4.14  */
#include<stdio.h>
int main(void)
{
	printf("Here's one way to print a ");
	printf("long string.\n");
	printf("Here's another way to print a "
	       "long string.\n");
	       
	       return 0;
}    

/*  4.15  */
#include<stdio.h>
int main(void)
{
	int age;
	float assets;
	char pet[30];
	
	printf("Enter your age, assets ,and favourite pet.\n");
	scanf("%d %f",&age,&assets);
	scanf("%s",pet);
	printf("%d $%.2f %s\n",age,assets,pet);
	
	return 0;
}      

/* 4.16  */
#include<stdio.h>
int main(void)
{
	unsigned width, precision;
	int number = 256;
	double weight = 242.5;
	
	printf("Enter a field width:\n");
	scanf("%d",&width);
	printf("The number is :%*d:\n",width,number);
	printf("Now enter a width and a precision:\n");
	scanf("%d %d",&width,&precision);
	printf("Weight = %*.*f\n",width,precision,weight);
	printf("Done!\n");
	
	return 0;
}         

/*   4.17  */
#include<stdio.h>
int main(void)
{
	int n;
	
	printf("Please enter three integers:\n");
	scanf("%*d %*d %d",&n);
	printf("The last integer was %d\n",n);
	
	return 0;
}