1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
#!/opt/local/bin/lua
--
-- See ../README.md
--
--
-- Run as: lua ch-1.lua < input-file
--
function int (x)
if x > 0 then
return math . floor (x)
else
return math . ceil (x)
end
end
function g2j (Y, M, D)
return (int ((1461 * (Y + 4800 + int ((M - 14) / 12))) / 4) +
int ((367 * (M - 2 - 12 * int ((M - 14) / 12))) / 12) -
int ((3 * int (((Y + 4900 + int ((M - 14) / 12)) / 100))) / 4) +
D - 32075)
end
function j2g (J)
local e = 4 * (J + 1401 +
int (int ((4 * J + 274277) / 146097) * 3 / 4) - 38) + 3
local D = int (((5 * (int ((e % 1461) / 4)) + 2) % 153) / 5) + 1
local M = ((int ((5 * (int ((e % 1461) / 4)) + 2) / 153) + 2) % 12) + 1
local Y = int (e / 1461) - 4716 + int ((12 + 2 - M) / 12)
return Y, M, D
end
local julian_today = g2j (2021, 9, 22)
local output_format = "%04d/%02d/%02d, %04d/%02d/%02d\n"
for line in io . lines () do
local _, _, Y, M, D = line : find ("([0-9]+)/([0-9]+)/([0-9]+)")
local julian_then = g2j (Y, M, D)
local Y1, M1, D1 = j2g (2 * julian_then - julian_today)
local Y2, M2, D2 = j2g (2 * julian_today - julian_then)
io . write (output_format : format (Y1, M1, D1, Y2, M2, D2))
end
|
