import struct, sys

path = "/home/aria/kellogg_remake/raw/PCKELL.DAT"
data = open(path, "rb").read()
print("total size:", len(data))

# Read uint16 LE values until they stop being monotonically non-decreasing
vals = []
off = 0
prev = -1
while off + 2 <= len(data):
    v = struct.unpack_from("<H", data, off)[0]
    vals.append(v)
    off += 2
    if len(vals) > 5000:
        break

# find longest monotonic non-decreasing prefix
mono_len = 1
for i in range(1, len(vals)):
    if vals[i] >= vals[i-1]:
        mono_len = i+1
    else:
        break

print("monotonic non-decreasing prefix length (uint16 entries):", mono_len)
print("that's byte offset:", mono_len*2)
print("first 40 vals:", vals[:40])
print("vals around break point:", vals[max(0,mono_len-10):mono_len+10])