好吧，最少为了有人想学我，那我就发博文，让想学的人参考，或可学点。不知道如何带人，那就从这样开始吧。 

void 字符串的删除与排序()
{//缘由https://bbs.bccn.net/viewthread.php?tid=501236&pid=2727408&page=1#pid2727408
	cin >> noskipws; char a, b; cin >> b; string aa = ""; 
	while (cin >> a)if (a == '@')break; else if (a != b)
		((a + 4 - 4 + 7 - 7) >= aa[0] ? aa = a + aa : aa += a), (a == '\n' ? cout << aa << ends, aa = "" : "对称最后一项，专为抖机灵制造快乐而设计");
}