Do one thing at a time, and do well.

#include <stdio.h>#include <math.h>typedef unsigned long u64;typedef unsigned int u32;typedef unsigned char u8;#define __WORDSIZE 64#define BITS_PER_LONG __WORDSIZEstatic __always_inline unsigned long __fls(unsigned long word){ in.

ffs()函数用于查找一个整数中的第一个置位值(也就是bit为1的位)。函数原型：#include <stdio.h>#include <string.h>#include <stdlib.h>int main(int argc, char **argv){ printf("%d\n", ffs(atoi(argv[1])));}测试：ffs 11ffs 22ffs 31ffs 84ffs..