Advent of Code 2015 Day 14

— Day 14: Reindeer Olympics —

Reindeer race!

Given the descriptions of each reindeer (in your puzzle input), after exactly 2503 seconds, what distance has the winning reindeer traveled?

with open('data-2015-14.txt', 'r') as f:
    inp = f.read().splitlines()

Let’s get that info into a list of lists

rein_list = [x.split(' ') for x in inp]

rein_info = [[x[0], int(x[3]), int(x[6]), int(x[13])] for x in rein_list]

tm = 2503

Now we race!

max_dist = 0

for r in rein_info:
    dist = 0
    time = 0
    while time <= tm:
        dist += r[1] * r[2] # travel
        time += r[2]        # travel time
        if time > tm:       # check for time while travelling
            dist -= (time - tm) * r[1]
        time += r[3]        # wait time
    # update maximum
    if dist > max_dist:
        max_dist = dist

max_dist

# 2696

2696

— Part Two —

Actually, Santa awards a point to each reindeer when they are in the lead.

Again given the descriptions of each reindeer (in your puzzle input), after exactly 2503 seconds, how many points does the winning reindeer have?

# keep a list of the distances travelled
dist_list = []

# calculate the distances at each step
# I like this countdown timer and travel switch
for r in rein_info:
    dist = []
    d = 0
    time = 0
    cd = r[2]
    travel = True
    while time < tm: 
        time += 1
        cd -= 1
        if travel:
            d += r[1] 
            dist.append(d)
        else: 
            dist.append(d)
        if cd == 0:
            if travel == True:
                cd = r[3]
                travel = False
            else:
                cd = r[2]
                travel = True
    # finished
    dist_list.append(dist)

Now let’s compare who is in the lead at each time step

dist_dict = {}
points_dict = {}

for k,v in zip(rein_info, dist_list):
    dist_dict[k[0]] = v
    points_dict[k[0]] = 0

for j in range(tm):
    m_r = ''
    m_d = 0
    for k in dist_dict.keys():
        if dist_dict[k][j] == m_d:
            m_r += ',' + k
        elif dist_dict[k][j] > m_d:
            m_d = dist_dict[k][j]
            m_r = k
    if ',' in m_r:
        for m in m_r.split(','):
            points_dict[m] += 1
            # print(m)
    else: 
        points_dict[m_r] += 1


points_dict

# 1084

{'Rudolph': 1084,
 'Cupid': 838,
 'Prancer': 24,
 'Donner': 277,
 'Dasher': 0,
 'Comet': 121,
 'Blitzen': 0,
 'Vixen': 13,
 'Dancer': 199}