C primer Plus Chap 03

C primer Plus 第三章代码与练习记录。

数据和C

• xt1.c

  /*整数上溢，浮点数上溢和浮点数下溢*/
  #include <stdio.h>
  int main(void)
  {
  	/*查看int的字长*/
  	printf("type int has a size of %lu bytes.\n",sizeof(int));
  	int intoverflow = 2147483647;
  	printf("the number is %d.\n",intoverflow);
  	intoverflow = intoverflow + 1;
  	printf("int overflow + 1 vavlue = %d.\n",intoverflow);
  	return 0;
  }

  输出结果：

  type int has a size of 4 bytes.
  the number is 2147483647.
  int overflow + 1 vavlue = -2147483648.

• xt2.c

  /*xt2.c--输入一个ASCII码值，输入相应的字符*/
  #include <stdio.h>
  int main(void)
  {
  	int number;
  	printf("please enter a number:\n");
  	scanf("%d",&number);
  	printf("the number %d is character %c.\n",number,number);
  	return 0;
  }

  输出结果：

  please enter a number:
  100
  the number 100 is character d.

• xt3.c

  /*xt3.c--编写程序发出警报声，并打印文字*/
  #include <stdio.h>
  int main(void)
  {
  	printf("\astartled by the sudden sound, sally shouted. \"by the great pumpkin, what was that!\"\n");
  	return 0;
  }

  输出结果：

  startled by the sudden sound, sally shouted. "by the great pumpkin, what was that!"

• xt4.c

  /*xt4.c--读入一个浮点数，分别以小数形式和指数形式打印*/
  #include <stdio.h>
  int main(void)
  {
  	float number;
  	printf("please enter a number:");
  	scanf("%f",&number);
  	printf("the number is %f.\n",number);
  	printf("the number %f can be writeen by %e.\n",number,number);
  	return 0;
  }

  输出结果：

  please enter a number:15
  the number is 15.000000.
  the number 15.000000 can be writeen by 1.500000e+01.

• xt5.c

  /*xt5.c*/
  #include <stdio.h>
  int main(void)
  {
  	double s = 3.156e7;
  	printf("%lf\n",s);
  	double secound,age;
  	printf("please enter your age:\n");
  	scanf("%lf",&age);
  	secound = s * age;
  	printf("your age %lf is %lf secound\n",age,secound);
  
  	return 0;
  }

  输出结果：

  31560000.000000
  please enter your age:
  33
  your age 33.000000 is 1041480000.000000 secound

• xt6.c

  #include <stdio.h>
  int main(void)
  {
  	float hydrone=3.0e-23;
  	float quart;
  	printf("please enter a number:\n");
  	scanf("%f",&quart);
  	printf("%e\n",(950*quart)/hydrone);
  
  	return 0;
  }

  输出结果：

  please enter a number:
  16
  5.066666e+26

• xt7.c

  #include <stdio.h>
  int main(void)
  {
  	float height;
  	printf("please enter your height\n");
  	scanf("%f",&height);
  	printf("your height %.2f inch is about %.2f cm.\n",height,height*2.54);
  	
  	return 0;
  }

  输出结果：

  please enter your height
  175
  your height 175.00 inch is about 444.50 cm.