DEV Community

Viper
Viper

Posted on • Edited on

Advent of Code 2021 Python Solution: Day 3

#adventofcode #python #algorithms #beginners

Again, I will be using helper function from part 1 to read my data.

Part 1 

from collections import Counter import numpy as np data,data1 = get_data(day=3) def part1(inp): cs = len(inp[0]) dt = [int(d) for dt in inp for d in dt] dt = np.array(dt).reshape(-1, cs) print(dt[0]) # sorted(x.items(), key=lambda item: item[1])  counts = [sorted(dict(Counter(dt[:, i])).items(), key=lambda item: item[1]) for i in range(len(dt[0]))] counts = np.array(counts).reshape(-1,2) # print(counts)  minidx = np.arange(0, len(counts), 2) maxidx = np.arange(1, len(counts), 2) minv = int("".join(list(map(str, counts[minidx, 0]))), 2) maxv = int("".join(list(map(str, counts[maxidx, 0]))), 2) print(minv, maxv) print(minv*maxv) part1(data)
Enter fullscreen mode Exit fullscreen mode

The output of above code will be:

[0 0 1 0 0] 9 22 198
Enter fullscreen mode Exit fullscreen mode

198 is a test output. The real output will be 4103154.

Part 2 

def o2(dt): ndt = dt.copy() #print(len(ndt[0]))  curr_c = 0 while curr_c<len(dt[0]): print(f"Current Col: {curr_c}") counts = [sorted(dict(Counter(ndt[:, curr_c])).items(), key=lambda item: item[1])] counts = np.array(counts).reshape(-1,2) if len(counts)>1: if counts[0, 1]==counts[1, 1]: ndt = ndt[ndt[:,curr_c]==1] else: ndt = ndt[ndt[:,curr_c]==counts[1][0]] else: ndt = ndt[ndt[:,curr_c]==counts[1][0]] print(f"Current Col: {curr_c} Rows: {len(ndt)}") # print(counts) # print(ndt[ndt[:,curr_c]==counts[1][0]])  curr_c+=1 res = int("".join(list(map(str, ndt[0]))), 2) print(res) return res def co2(dt): ndt = dt.copy() #print(len(ndt[0]))  curr_c = 0 while curr_c<len(dt[0]): counts = [sorted(dict(Counter(ndt[:, curr_c])).items(), key=lambda item: item[1])] counts = np.array(counts).reshape(-1,2) if len(counts)>1: if counts[0, 1]== counts[1, 1]: ndt = ndt[ndt[:,curr_c]==0] else: ndt = ndt[ndt[:,curr_c]==counts[0][0]] else: ndt = ndt[ndt[:,curr_c]==counts[0][0]] # print(ndt)  print(f"Current Col: {curr_c} Rows: {len(ndt)}") curr_c+=1 return int("".join(list(map(str, ndt[0]))), 2) def part2(inp): cs = len(inp[0]) dt = [int(d) for dt in inp for d in dt] dt = np.array(dt).reshape(-1, cs) print("O2") o2v = o2(dt) co2v = co2(dt) print(o2v, co2v) print(o2v*co2v) part2(data1)
Enter fullscreen mode Exit fullscreen mode

The output will be:

O2 Current Col: 0 Current Col: 0 Rows: 511 Current Col: 1 Current Col: 1 Rows: 263 Current Col: 2 Current Col: 2 Rows: 134 Current Col: 3 Current Col: 3 Rows: 71 Current Col: 4 Current Col: 4 Rows: 36 Current Col: 5 Current Col: 5 Rows: 20 Current Col: 6 Current Col: 6 Rows: 12 Current Col: 7 Current Col: 7 Rows: 8 Current Col: 8 Current Col: 8 Rows: 5 Current Col: 9 Current Col: 9 Rows: 3 Current Col: 10 Current Col: 10 Rows: 2 Current Col: 11 Current Col: 11 Rows: 1 3399 Current Col: 0 Rows: 489 Current Col: 1 Rows: 235 Current Col: 2 Rows: 109 Current Col: 3 Rows: 54 Current Col: 4 Rows: 24 Current Col: 5 Rows: 11 Current Col: 6 Rows: 4 Current Col: 7 Rows: 2 Current Col: 8 Rows: 1 Current Col: 9 Rows: 1 Current Col: 10 Rows: 1 Current Col: 11 Rows: 1 3399 1249 4245351
Enter fullscreen mode Exit fullscreen mode

All of my codes are available in GitHub as Jupyter Notebook.

Why not read more?

Top comments (0)