AoC 2023, day 14, part 1 (dc)

# Command: perl -pe's/(.)/$1 /g;y/.O#/012/' <input | dc -fpart1.dc

?
zdsn                                # n = size; i = n
[
    d 2 r:a                         # a(i) = 2
    1- d0<I
] dsIx
+                                   # clear i (+0)

[
    [
        z d;a 3* 3R+ r:a            # a(z) = 3*a(z) + top
        z0<L
    ] dsLx
    ? z0<M
] dsMx

[ lc1+sc ] sC

# Score: i h a(i) -> i h a(i)
[
    rd lcd                          # a(i) h  h c c
    3R2* r- 1+ *                    # a(i) h  c*(2h-c+1)
    2/
    ls+ss
    0sc
    r
] sS

ln                                  # i=n
[
    d;a 0r                          # i h=0 a(i)
    [
        3~                          # h a(i)=a(i)/3 val=a(i)%3
        d 1=C                       # count if val == 1
          2=S                       # score if val == 0; stack: h a(i)
        r1+r                        # h++
        d 0<H                       # loop if a(i) non-zero
    ] dsHx

    # stack: i h 0
    *+                              # clear 2 (+ 0*h)
    1- d0<I
] dsIx

[Part 1: ]nlsp