Day 12

Author: Florian Rohrer

README.md

@@ -2,17 +2,18 @@
 
 |Exercise Description|Solution|
 |:---|:---|
-|[Day 1: Calorie Counting](https://adventofcode.com/2022/day/1)        |[py](/day01/main.py)|
-|[Day 2: Rock Paper Scissors](https://adventofcode.com/2022/day/2)     |[py](/day02/main.py), [alt1](/day02/alt1.py), [alt2](/day02/alt2.py)|
-|[Day 3: Rucksack Reorganization](https://adventofcode.com/2022/day/3) |[py](/day03/main.py)|
-|[Day 4: Camp Cleanup](https://adventofcode.com/2022/day/4)            |[py](/day04/main.py)|
-|[Day 5: Supply Stacks](https://adventofcode.com/2022/day/5)           |[py](/day05/main.py)|
-|[Day 6: Tuning Trouble](https://adventofcode.com/2022/day/6)          |[py](/day06/main.py), [alt](/day06/alt.py)|
-|[Day 7: No Space Left On Device](https://adventofcode.com/2022/day/7) |[py](/day07/main.py), [alt](/day07/alt.py)|
-|[Day 8: Treetop Tree House](https://adventofcode.com/2022/day/8)      |[py](/day08/main.py)|
-|[Day 9: Rope Bridge](https://adventofcode.com/2022/day/9)             |[py](/day09/main.py)|
-|[Day 10: Cathode-Ray Tube](https://adventofcode.com/2022/day/10)      |[py](/day10/main.py)|
-|[Day 11: Monkey in the Middle](https://adventofcode.com/2022/day/11)  |[py](/day11/main.py)|
+|[Day 1: Calorie Counting](https://adventofcode.com/2022/day/1)          |[py](/day01/main.py)|
+|[Day 2: Rock Paper Scissors](https://adventofcode.com/2022/day/2)       |[py](/day02/main.py), [alt1](/day02/alt1.py), [alt2](/day02/alt2.py)|
+|[Day 3: Rucksack Reorganization](https://adventofcode.com/2022/day/3)   |[py](/day03/main.py)|
+|[Day 4: Camp Cleanup](https://adventofcode.com/2022/day/4)              |[py](/day04/main.py)|
+|[Day 5: Supply Stacks](https://adventofcode.com/2022/day/5)             |[py](/day05/main.py)|
+|[Day 6: Tuning Trouble](https://adventofcode.com/2022/day/6)            |[py](/day06/main.py), [alt](/day06/alt.py)|
+|[Day 7: No Space Left On Device](https://adventofcode.com/2022/day/7)   |[py](/day07/main.py), [alt](/day07/alt.py)|
+|[Day 8: Treetop Tree House](https://adventofcode.com/2022/day/8)        |[py](/day08/main.py)|
+|[Day 9: Rope Bridge](https://adventofcode.com/2022/day/9)               |[py](/day09/main.py)|
+|[Day 10: Cathode-Ray Tube](https://adventofcode.com/2022/day/10)        |[py](/day10/main.py)|
+|[Day 11: Monkey in the Middle](https://adventofcode.com/2022/day/11)    |[py](/day11/main.py)|
+|[Day 12: Hill Climbing Algorithm](https://adventofcode.com/2022/day/12) |[py](/day12/main.py)|
 
 My solutions from previous years:
 * [r0f1/adventofcode2020](https://github.com/r0f1/adventofcode2020)

day12/main.py

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+from networkx import grid_2d_graph
+from networkx import shortest_path
+
+with open("input.txt") as f:
+    grid = [list(x.strip()) for x in f]
+
+source = None
+all_sources = []
+target = None
+for row_n, row in enumerate(grid):
+    for col_n, c in enumerate(row):
+        if c == "S":
+            source = (row_n, col_n)
+            grid[row_n][col_n] = "a"
+        if c == "E":
+            target = (row_n, col_n)
+            grid[row_n][col_n] = "z"
+        if grid[row_n][col_n] == "a":
+            all_sources.append((row_n, col_n))
+
+g = grid_2d_graph(len(grid), len(grid[0]))
+
+grid = [[ord(c)-ord("a") for c in row] for row in grid]
+def weight_func(a, b, edge_dict):
+    if grid[a[0]][a[1]] < grid[b[0]][b[1]] - 1:
+        return None
+    return 1
+
+print(len(shortest_path(g, source, target, weight_func))-1)
+
+paths = []
+for s in all_sources:
+    try:
+        paths.append(len(shortest_path(g, s, target, weight_func))-1)
+    except:
+        pass
+print(min(paths))