1.5.2数据类型实验
实验A1:表达式11111*11111的值是多少?把5个1改成6个1呢?9个1呢?
实验A2:把实验A1中的所有数换成浮点数,结果如何?
实验A3:表达式sqrt(-10)的值是多少?尝试用各种方式输出。在计算的过程中系统会报错吗?
实验A4:表达式1.0/0.0、0.0/0.0的值是多少?尝试用各种方式输出。在计算的过程中系统会报错吗?
实验A5:表达式1/0的值是多少?在计算的过程中系统会报错吗?
#include<stdio.h>
#include<math.h>
int main()
{
//A1
printf("%u\n", 11111*11111);
printf("%lu\n", 111111L*111111L); //xxx
printf("%lld\n", 111111111L*111111111L); //xxx
//A2
printf("%f\n", 11111.0*11111.0);
printf("%lf\n", 111111.0*111111.0); //xxx
printf("%lf\n", 111111111.0*111111111.0); //xxx
//A3
printf("%f\n", sqrt(-10));
//A4
printf("%u\n", 1.0/0.0);
printf("%f\n", 1.0/0.0);
//A5
// warning: division by zero [-Wdiv-by-zero]
//printf("%u\n", 1/0);
}
/*
123454321
12345654321
12345678987654321
123454321.000000
12345654321.000000
12345678987654320.000000
nan
0
inf
*/
思考问题
问题1:int型整数的最小值和最大值是多少(需要精确值)?
问题2:double型浮点数能精确到多少位小数?或者,这个问题本身值得商榷?
问题3:double型浮点数最大正数值和最小正数值分别是多少(不必特别精确)?
#include<stdio.h>
int main()
{
int max_int = 1, min_int = -1, last_int = 0;
while (max_int > last_int)
{
last_int = max_int;
max_int++;
}
printf("max_int: %d\n", last_int);
last_int = 0;
while (min_int < last_int)
{
last_int = min_int;
min_int--;
}
printf("min_int: %d\n", last_int);
double frac_part = 0.1234567890123456789012345678901234567890f;
printf("%.200lf\n", frac_part);
double max_double = 1, min_u_double = 1, last_double = 0;
while (max_double > last_double)
{
last_double = max_double;
max_double *= 10;
printf("max_double: %lf\n", last_double);
}
last_double = 2;
while (min_u_double < last_double)
{
last_double = min_u_double;
min_u_double /= 10;
printf("min_unsigned double: %.200lf\n", last_double);
}
}
/*
max_int: 2147483647
min_int: -2147483648
0.12345679104328155517578125000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
(小数点8位后就不准了)
max_double: 99999999999999981139503267596847425176765180000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000.000000
max_double: inf
min_unsigned double: 0.00000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
(小数点43位)
*/