位于，memcpy

# include <iostream># include <stdlib.h># include <stdio.h># include <string.h>using namespace std;typedef struct AA{int b1:5;int b2:2;} AA;//sizeof（AA）  大小为4int main(void){AA aa;char cc[100];strcpy(cc, "0123456789abcdefghijklmnopqrstuvwxyz");memcpy(&aa, cc, sizeof(AA));//aa的四字节所存放的值：0 1 2 3的ascll码即00110000,00110001,00110010,00110011//最后输出的是这４个字节的前５位，和之后的２位分别为：10000,和01cout << aa.b1 << endl;cout << aa.b2 << endl;return 0;}