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Day 2

Dive!

view the Advent of Code 2021 Day 2 challenge

Setup

# Setup - load any packages
import pandas as pd

Load the data

# load data into Pandas DataFrame
data_raw = pd.read_csv('day2_data.txt',delimiter=' ', index_col=False, header=None)

# Add column names
data_raw.columns =['direction', 'distance']

# Check the data types of the columns
print(data_raw.dtypes)

# set the direction column as the index
data_raw=data_raw.set_index('direction')

# View the first few rows of the data
data_raw.head()

direction    object
distance      int64
dtype: object

	distance
direction
forward	2
down	9
up	6
forward	1
down	5

Part 1

# copy the raw data for use in part 1
part1=data_raw.copy()

# variables to store the distance and depth
distance=0
depth=0

# Group by the direction to get the overal distances
part1=part1.groupby(['direction']).sum()

# view the group by results
print(part1.head())

# set the distance
distance=part1.loc['forward'][0]

# set the depth
depth = depth + part1.loc['down'][0] - part1.loc['up'][0] 

print(f'distance = {distance} depth = {depth}')

position = distance * depth

print (f'answer = {position}')

           distance
direction          
down           1991
forward        2010
up              961
distance = 2010 depth = 1030
answer = 2070300

Part 2

view the Advent of Code 2021 Day 2 challenge Part 2

# copy the raw data for use in part 2
part2=data_raw.copy()

# Drop the index
part2.reset_index(drop=False, inplace=True)

# declare variables to store the distance, depth and aim
p2_dist=0
p2_depth=0
p2_aim=0

# itterate through each row of directions
for index, row in part2.iterrows():
    if (row['direction']=='forward'):
        #increase distance
        p2_dist += row['distance']
        
        # check aim of submarine
        if p2_aim!= 0:
            # not aiming forward so increase/decrease depth by aim
            p2_depth = p2_depth + (row['distance'] * p2_aim)
    elif (row['direction']=='down'):
        # increase aim
        p2_aim=p2_aim + row['distance']
    elif (row['direction']=='up'):
        # deincrease aim
        p2_aim=p2_aim - row['distance']
        
p2_position = p2_dist * p2_depth
print (f'answer = {p2_position}')

answer = 2078985210