您可以通过将底部数字左移7位，然后对结果和第一个数字执行按位OR来实现此操作。

unsigned int a = 0x3f;
unsigned int b = 0x06;
unsigned int result = (b << 7) | a;

unsigned int X = 0b00111111;
unsigned int Y = 0b00000110;

unsigned int Z = ((X << 7) & 0xFF00) | Y;

unsigned char a = 0b00000110;
unsigned char b = 0b01111111;
unsigned short c = (b << 8); // shift everything left 8 bits to set the high bits
c &= 0xFF00; // clear out the lower bits - not necessary in C
c |= a; // set the lower 8 bits

int a = 0b0111111;
int b = 0b0000110;

int combined = (a << 7) | b;