diff --git a/011/grid.txt b/011/grid.txt new file mode 100644 index 0000000..4ac2451 --- /dev/null +++ b/011/grid.txt @@ -0,0 +1,20 @@ +08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08 +49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00 +81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65 +52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91 +22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80 +24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50 +32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70 +67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21 +24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72 +21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95 +78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92 +16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57 +86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58 +19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40 +04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66 +88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69 +04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36 +20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16 +20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54 +01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48 diff --git a/011/main.rs b/011/main.rs new file mode 100644 index 0000000..96e0c5c --- /dev/null +++ b/011/main.rs @@ -0,0 +1,105 @@ +use std::fs::File; +use std::io::{ self, BufRead, BufReader }; + +type Grid = Vec>; +const N: usize = 20; + +fn read_grid_lines() -> io::Lines> { + let file = File::open("grid.txt").unwrap(); + return io::BufReader::new(file).lines(); +} + +fn get_grid() -> Grid { + let lines = read_grid_lines(); + let mut grid: Grid = Vec::new(); + for line in lines { + let s = line.unwrap(); + let ns: Vec<_> = s.split(" ") + .map(|x| x.parse::().unwrap()) + .collect(); + grid.push(ns); + } + return grid; +} + +fn g(grid: &Grid, i: usize, j: usize) -> u32 { + return u32::from(grid.get(i).unwrap().get(j).unwrap().clone()); +} + +fn best_h(grid: &Grid) -> u32 { + let mut best_pr = 1; + for i in 0..N { + for j in 0..N-3 { + let a = g(&grid, i, j); + let b = g(&grid, i, j + 1); + let c = g(&grid, i, j + 2); + let d = g(&grid, i, j + 3); + let pr = a * b * c * d; + if pr > best_pr { best_pr = pr; } + } + } + return best_pr; +} + +fn best_v(grid: &Grid) -> u32 { + let mut best_pr = 1; + for i in 0..N-3 { + for j in 0..N { + let a = g(&grid, i, j); + let b = g(&grid, i + 1, j); + let c = g(&grid, i + 2, j); + let d = g(&grid, i + 3, j); + let pr = a * b * c * d; + if pr > best_pr { best_pr = pr; } + } + } + return best_pr; +} + +fn best_dr(grid: &Grid) -> u32 { + let mut best_pr = 1; + for i in 0..N-3 { + for j in 0..N-3 { + let a = g(&grid, i, j); + let b = g(&grid, i + 1, j + 1); + let c = g(&grid, i + 2, j + 2); + let d = g(&grid, i + 3, j + 3); + let pr = a * b * c * d; + if pr > best_pr { best_pr = pr; } + } + } + return best_pr; +} + +fn best_dl(grid: &Grid) -> u32 { + let mut best_pr = 1; + for i in 3..N { + for j in 0..N-3 { + let a = g(&grid, i, j); + let b = g(&grid, i - 1, j + 1); + let c = g(&grid, i - 2, j + 2); + let d = g(&grid, i - 3, j + 3); + let pr = a * b * c * d; + if pr > best_pr { best_pr = pr; } + } + } + return best_pr; +} + +fn best(grid: &Grid) -> u32 { + let a = best_h(&grid); + let b = best_v(&grid); + let c = best_dr(&grid); + let d = best_dl(&grid); + + println!("{} {} {} {}", a, b, c, d); + + return best_h(&grid).max(best_v(&grid)).max(best_dr(&grid)).max(best_dl(grid)); +} + +fn main() { + let grid = get_grid(); + let n = best(&grid); + + println!("{}", n); +}