C 基础教程

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C 语言实例 - 计算 int, float, double 和 char 字节大小

C 语言实例

1计算 long long, long double 字节大小

使用 sizeof 操作符计算int, float, double 和 char四种变量字节大小。

sizeof 是 C 语言的一种单目操作符，如C语言的其他操作符++、--等，它并不是函数。

sizeof 操作符以字节形式给出了其操作数的存储大小。


#include <stdio.h>
 
int main()
{
    int integerType;
    float floatType;
    double doubleType;
    char charType;
 
    // sizeof 操作符用于计算变量的字节大小
    printf("Size of int: %ld bytes\n",sizeof(integerType));
    printf("Size of float: %ld bytes\n",sizeof(floatType));
    printf("Size of double: %ld bytes\n",sizeof(doubleType));
    printf("Size of char: %ld byte\n",sizeof(charType));
 
    return 0;
}

运行结果：

Size of int: 4 bytes
Size of float: 4 bytes
Size of double: 8 bytes
Size of char: 1 byte

计算 long long, long double 字节大小


#include <stdio.h>
int main()
{
    int a;
    long b;
    long long c;
 
    double e;
    long double f;
 
 
    printf("Size of int = %ld bytes \n", sizeof(a));
    printf("Size of long = %ld bytes\n", sizeof(b));
    printf("Size of long long = %ld bytes\n", sizeof(c));
 
    printf("Size of double = %ld bytes\n", sizeof(e));
    printf("Size of long double = %ld bytes\n", sizeof(f));
 
    return 0;
}

运行结果：

Size of int = 4 bytes 
Size of long = 8 bytes
Size of long long = 8 bytes
Size of double = 8 bytes
Size of long double = 16 bytes