C 型態

C data types 分成整數(二補數), 浮點數(IEEE754)

#include <stdio.h>
int main(int argc, char *argv[])
{
    printf("char size=%ld\n",sizeof(char));
    printf("signed char size=%ld\n",sizeof(signed char));
    printf("unsigned char size=%ld\n",sizeof(unsigned char));
    printf("short size=%ld\n",sizeof(short));
    printf("short int size=%ld\n",sizeof(short int));
    printf("signed short size=%ld\n",sizeof(signed short));
    printf("signed short int size=%ld\n",sizeof(signed short int));
    printf("unsigned short size=%ld\n",sizeof(unsigned short));
    printf("unsigned short int size=%ld\n",sizeof(unsigned short int));
    printf("int size=%ld\n",sizeof(int));
    printf("signed int size=%ld\n",sizeof(signed int));
    printf("unsigned size=%ld\n",sizeof(unsigned));
    printf("unsigned int size=%ld\n",sizeof(unsigned int));
    printf("long size=%ld\n",sizeof(long));
    printf("long int size=%ld\n",sizeof(long int));
    printf("signed long size=%ld\n",sizeof(signed long));
    printf("signed long int size=%ld\n",sizeof(signed long int));
    printf("unsigned long size=%ld\n",sizeof(unsigned long));
    printf("unsigned long int size=%ld\n",sizeof(unsigned long int));
    printf("long long size=%ld\n",sizeof(long long));
    printf("long long int size=%ld\n",sizeof(long long int));
    printf("signed long long size=%ld\n",sizeof(signed long long));
    printf("signed long long int size=%ld\n",sizeof(signed long long int));
    printf("unsigned long long size=%ld\n",sizeof(unsigned long long));
    printf("unsigned long long int size=%ld\n",sizeof(unsigned long long int));
    printf("float size=%ld\n",sizeof(float));
    printf("double size=%ld\n",sizeof(double));
    printf("long double size=%ld\n",sizeof(long double));

    // 32bit CPU 指標佔4byte , 64bit CPU 佔 8byte
    printf("\n\n\n\nchar* size=%ld\n",sizeof(char*));
    printf("signed char* size=%ld\n",sizeof(signed char*));
    printf("unsigned char* size=%ld\n",sizeof(unsigned char*));
    printf("short* size=%ld\n",sizeof(short*));
    printf("short int* size=%ld\n",sizeof(short int*));
    printf("signed short* size=%ld\n",sizeof(signed short*));
    printf("signed short int* size=%ld\n",sizeof(signed short int*));
    printf("unsigned short* size=%ld\n",sizeof(unsigned short*));
    printf("unsigned short int* size=%ld\n",sizeof(unsigned short int*));
    printf("int* size=%ld\n",sizeof(int*));
    printf("signed int* size=%ld\n",sizeof(signed int*));
    printf("unsigned* size=%ld\n",sizeof(unsigned*));
    printf("unsigned int* size=%ld\n",sizeof(unsigned int*));
    printf("long* size=%ld\n",sizeof(long*));
    printf("long int* size=%ld\n",sizeof(long int*));
    printf("signed long* size=%ld\n",sizeof(signed long*));
    printf("signed long int* size=%ld\n",sizeof(signed long int*));
    printf("unsigned long* size=%ld\n",sizeof(unsigned long*));
    printf("unsigned long int* size=%ld\n",sizeof(unsigned long int*));
    printf("long long* size=%ld\n",sizeof(long long*));
    printf("long long int* size=%ld\n",sizeof(long long int*));
    printf("signed long long* size=%ld\n",sizeof(signed long long*));
    printf("signed long long* int size=%ld\n",sizeof(signed long long int*));
    printf("unsigned long long* size=%ld\n",sizeof(unsigned long long*));
    printf("unsigned long long int* size=%ld\n",sizeof(unsigned long long int*));
    printf("float* size=%ld\n",sizeof(float*));
    printf("double* size=%ld\n",sizeof(double*));
    printf("long double* size=%ld\n",sizeof(long double*));
    printf("void* size=%ld\n",sizeof(void*));

    return 0;
}

C data types

Type	Explanation	Format Specifier
`char`	Smallest addressable unit of the machine that can contain basic character set. It is an integer type. Actual type can be either signed or unsigned depending on the implementation.	%c
`signed char`	Of the same size as `char`, but guaranteed to be signed.	%c (or %hhi for numerical output)
`unsigned char`	Of the same size as `char`, but guaranteed to be unsigned.	%c (or %hhu for numerical output)
`short` `short int` `signed short` `signed short int`	Short signed integer type. Capable of containing at least the [−32767,+32767] range;^[3] thus, it is at least 16 bits in size.	%hi
`unsigned short` `unsigned short int`	The same as `short`, but unsigned.	%hu
`int` `signed int`	Basic signed integer type. Capable of containing at least the [−32767,+32767] range;^[3] thus, it is at least 16 bits in size.	%i or %d
`unsigned` `unsigned int`	The same as `int`, but unsigned.	%u
`long` `long int` `signed long` `signed long int`	Long signed integer type. Capable of containing at least the [−2147483647,+2147483647] range;^[3] thus, it is at least 32 bits in size.	%li
`unsigned long` `unsigned long int`	The same as `long`, but unsigned.	%lu
`long long` `long long int` `signed long long` `signed long long int`	Long long signed integer type. Capable of containing at least the [−9223372036854775807,+9223372036854775807] range;^[3] thus, it is at least 64 bits in size. Specified since the C99 version of the standard.	%lli
`unsigned long long` `unsigned long long int`	The same as `long long`, but unsigned. Specified since the C99 version of the standard.	%llu
`float`	Real floating-point type, usually referred to as a single-precision floating-point type. Actual properties unspecified (except minimum limits), however on most systems this is the IEEE 754 single-precision binary floating-point format. This format is required by the optional Annex F "IEC 60559 floating-point arithmetic".	%f (promoted automatically to `double` for `printf()`)
`double`	Real floating-point type, usually referred to as a double-precision floating-point type. Actual properties unspecified (except minimum limits), however on most systems this is the IEEE 754 double-precision binary floating-point format. This format is required by the optional Annex F "IEC 60559 floating-point arithmetic".	%f (%lf for `scanf()`)
`long double`	Real floating-point type, usually mapped to an extended precision floating-point number format. Actual properties unspecified. Unlike types `float` and `double`, it can be either 80-bit floating point format, the non-IEEE "double-double" or IEEE 754 quadruple-precision floating-point format if a higher precision format is provided, otherwise it is the same as `double`. See the article on long double for details.	%Lf