L = 7m + 3 - x - (x/4)_w + 10 + (c - 16) - ((c - 16) / 4)_w;
that is, since 3 + 10 = 13 or 6 (the 7 days being rejected, as they do not
affect the value of L),
Encyclopaedia Britannica, 11th Edition, "Bulgaria" to "Calgary" Volume 4, Part 4 · 第 53 / 71 题