Solving Advent of Code 2019-08 with R and JavaScript.
[Disclaimer] Obviously, this post contains a big spoiler about Advent of Code, as it gives solutions for solving day 8.
Instructions
Find the instructions at: https://adventofcode.com/2019/day/8
R solution
Part one
library(magrittr)
library(purrr)
ipt <- read.delim("input8.txt", header = FALSE, colClasses = "character")$V1
ipt <- strsplit(ipt, "")[[1]] %>% as.numeric()
layers_size <- 6 * 25
l <- list()
for (i in 1: (length(ipt)/layers_size)){
l[[i]] <- ipt[1:150]
ipt <- ipt[151:length(ipt)]
}
mn <- l %>%
lapply(table) %>%
map_dbl("0") %>%
which.min()
l[[mn]] %>%
table()
## .
## 0 1 2
## 7 14 129
14 * 129
## [1] 1806
Part two
v <- c()
for (i in seq_len(layers_size)){
idx <- map_dbl(l, i)
v[i] <- idx[idx %in% c(0,1)][1]
}
library(dplyr)
library(tidyr)
library(ggplot2)
library(tibble)
matrix(v, ncol = 6) %>%
as.data.frame() %>%
rowid_to_column() %>%
gather(key = key, value = value, V1:V6) %>%
mutate(key = gsub("V(.)", "\\1", key) %>% as.numeric()) %>%
ggplot(aes(rowid, key, fill = as.factor(value))) +
geom_tile() +
coord_fixed() +
scale_fill_viridis_d() +
scale_y_reverse()
JS solution
var ipt = fs.readFileSync("input8.txt", 'utf8').split("").filter(x => x.length != 0 & x != '\n').map(x => parseInt(x));
var layers_size = 6 * 25;
var layer_n = ipt.length / layers_size;
var res = [];
function table(vec){
var tbl = {};
vec.map(function(x){
if (tbl[x]){
tbl[x] = tbl[x] + 1;
} else {
tbl[x] = 1;
}
})
return tbl;
}
for (var i = 0; i < layer_n; i ++){
res[i] = ipt.splice(0, layers_size);
}
var res_b = res.map(x => table(x));
var minim = Math.min.apply(Math, res_b.map(x => x['0']));
var smallest = res_b.filter(x => x['0'] == minim);
smallest[0]["1"] * smallest[0]["2"];
## 1806
var v = [];
for (var i = 0; i < layers_size; i ++){
var idx = res.map(x => x[i]);
v[i] = idx.find(z => z== 0 | z == 1);
}
var nn = [];
for (var i = 0; i < 6; i ++){
nn[i] = v.splice(0, 25).join(" ").replace(/0/g, " ");
}
nn
## [ ' 1 1 1 1 1 1 1 1 1 1 1 1 1 ',
## ' 1 1 1 1 1 1 1 1 ',
## ' 1 1 1 1 1 1 1 1 1 1 ',
## ' 1 1 1 1 1 1 1 1 1 1 1 1 1 ',
## '1 1 1 1 1 1 1 1 1 ',
## ' 1 1 1 1 1 1 1 1 1 ' ]
Top comments (0)