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Day 7

The Treachery of Whales

view the Advent of Code 2021 Day 7 challenge

Setup

# Setup - load any packages
import numpy as np

Load the data

def LoadData(filename):
    return np.loadtxt(filename, dtype='int', delimiter=',')

day7_raw=LoadData('day7_data.txt')

Part 1

def CalculatePart2Fuel(distance):
    return int((distance*(distance+1))/2)

def CalculateFuel(positions, new_location, Part1):
    # variable to store the fuel needed
    fuel=0
    
    #loop through each position and caluclate the cost to move it to the new location
    for location in positions:
        # calculate distance between current and new location
        distance = abs(location - new_location)
        if Part1==True:
            fuel=fuel + distance
        else:
            # Calculate increased fuel cost
            fuel=fuel + CalculatePart2Fuel(distance)
    # return the fuel calculation
    return fuel

def CalculateBestPosition(positions, Part1=True):
    # Set default best fuel value
    best_fuel=999999999
    
    #loop through each possible value between min and max position
    for i in range(positions.min(), positions.max()+1):
        temp_fuel=CalculateFuel(positions, i, Part1)
        if temp_fuel< best_fuel:
            best_fuel=temp_fuel
    return best_fuel

p1_answer=CalculateBestPosition(day7_raw)
print(f'answer = {p1_answer}') 

answer = 356179

Part 2

view the Advent of Code 2021 Day 6 challenge Part 2

p2_answer=CalculateBestPosition(day7_raw, False)
print(f'answer = {p2_answer}') 

answer = 99788435