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机器平台：X86_64 处理器 操作系统：Red Hat 4.1.2-14 编译器： gcc version 4.1.2 20070626
Size of char is: 1 Size of unsigned char is: 1 Size of signed char is: 1
Size of int is: 4 Size of short is: 2 Size of long is: 8 Size of long int is: 8 Size of signed int is: 4 Size of unsigned int is: 4 Size of unsigned long int is: 8 Size of long long int is: 8 Size of unsigned long long is: 8
Size of float is: 4
Size of double is: 8
Size of long double is: 16
Size of (void *) is: 8 Size of (char *) is: 8 Size of (int *) is: 8 Size of (long *) is: 8 Size of (long long *) is: 8 Size of (float *) is: 8 Size of (double *) is: 8 所有指针都是占8字节
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机器平台： X86_32 处理器 操作系统： Windows XP SP2 编译器： VS2005自带的C++编译器
Size of char is: 1 Size of unsigned char is: 1 Size of signed char is: 1
Size of int is: 4 Size of short is: 2 Size of long is: 4 Size of long int is: 4 Size of signed int is: 4 Size of unsigned int is: 4 Size of unsigned long int is: 4 Size of long long int is: 8 Size of unsigned long long is: 8
Size of float is: 4 Size of double is: 8 Size of long double is: 8
Size of (void *) is: 4 Size of (char *) is: 4 Size of (int *) is: 4 Size of (long *) is: 4 Size of (long long *) is: 4 Size of (float *) is: 4 Size of (double *) is: 4 所有指针都是占4字节 sizeof()用法汇总 sizeof()功能：计算数据空间的字节数 1.与strlen()比较 strlen()计算字符数组的字符数，以"\0"为结束判断，不计算为'\0'的数组元素。 而sizeof计算数据（包括数组、变量、类型、结构体等）所占内存空间，用字节数表示。 2.指针与静态数组的sizeof操作 指针均可看为变量类型的一种。所有指针变量的sizeof 操作结果均为4。 注意：int *p; sizeof(p)=4; 但sizeof(*p)相当于sizeof(int); 对于静态数组，sizeof可直接计算数组大小； 例：int a[10];char b[]="hello"; sizeof(a)等于4*10=40; sizeof(b)等于6; 注意：数组做型参时，数组名称当作指针使用！！ void fun(char p[]) {sizeof(p)等于4} 经典问题： double* (*a)[3][6]; cout char a; char b; int c; double d; }; cout double d; }; struct s3 { s1 s; char a; }; struct s4 { s2 s; char a; }; cout |
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