long genrndnum（ long lower_limit，long upper_limit）

{

srand（time（NULL））; //< ==================错误在这里

long rdnum = 0;



rdnum = lower_limit +（rand（）％（int）（upper_limit - lower_limit + 1））;



返回rdnum;

}

long genrndnum(long lower_limit,long upper_limit)
{
srand(time(NULL)); //<================== mistake here
long rdnum =0;

rdnum = lower_limit + (rand() % (int)(upper_limit - lower_limit + 1));

return rdnum;
}

每次需要新的随机数时，不应该调用 srand 。您应该在第一次调用 rand 之前调用一次。

You should not call srand every time you need a new random number. You should call it once, before calling rand for the very first time.