一道输出的笔试题

#include <stdio.h>

int main()
{
    unsigned char a = 127;
    char b = a+1;
    short c = a+1;
    long d = a+1;
    double e = a+1;
    printf("0x%x, 0x%x, 0x%x, 0x%x\n", b, c, d, e);
    return 0;
}


0xffffff80, 0x80, 0x80, 0x0