AoC 2025 Day 7 - bash

Author: pareronia

README.md

@@ -10,7 +10,7 @@
 | ---| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
 | python3 | [✓](src/main/python/AoC2025_01.py) | [✓](src/main/python/AoC2025_02.py) | [✓](src/main/python/AoC2025_03.py) | [✓](src/main/python/AoC2025_04.py) | [✓](src/main/python/AoC2025_05.py) | [✓](src/main/python/AoC2025_06.py) | [✓](src/main/python/AoC2025_07.py) |  |  |  |  |  |
 | java | [✓](src/main/java/AoC2025_01.java) | [✓](src/main/java/AoC2025_02.java) | [✓](src/main/java/AoC2025_03.java) | [✓](src/main/java/AoC2025_04.java) | [✓](src/main/java/AoC2025_05.java) | [✓](src/main/java/AoC2025_06.java) | [✓](src/main/java/AoC2025_07.java) |  |  |  |  |  |
-| bash | [✓](src/main/bash/AoC2025_01.sh) | [✓](src/main/bash/AoC2025_02.sh) | [✓](src/main/bash/AoC2025_03.sh) | [✓](src/main/bash/AoC2025_04.sh) | [✓](src/main/bash/AoC2025_05.sh) | [✓](src/main/bash/AoC2025_06.sh) |  |  |  |  |  |  |
+| bash | [✓](src/main/bash/AoC2025_01.sh) | [✓](src/main/bash/AoC2025_02.sh) | [✓](src/main/bash/AoC2025_03.sh) | [✓](src/main/bash/AoC2025_04.sh) | [✓](src/main/bash/AoC2025_05.sh) | [✓](src/main/bash/AoC2025_06.sh) | [✓](src/main/bash/AoC2025_07.sh) |  |  |  |  |  |
 <!-- @END:ImplementationsTable:2025@ -->
 
 ## 2024

src/main/bash/AoC2025_07.sh

@@ -0,0 +1,86 @@
+#!/bin/bash
+#
+# Advent of Code 2025 Day 7
+#
+
+year=2025
+day=07
+
+solve() {
+    local -i part="$1"
+
+    declare -a dp
+    local -i ans1=0
+    local -i first=1
+    while read -r line || [ -n "$line" ]; do
+        if ((first == 1)); then
+            for ((i = 0; i < "${#line}"; i++)); do
+                if [ "${line:i:1}" = 'S' ]; then
+                    dp+=(1)
+                else
+                    dp+=(0)
+                fi
+            done
+            ((first = 0))
+        else
+            for ((i = 0; i < "${#line}"; i++)); do
+                if [ "${line:i:1}" = '^' ]; then
+                    ((dp[i] > 0)) && ((ans1++))
+                    ((dp[i - 1] += dp[i]))
+                    ((dp[i + 1] += dp[i]))
+                    ((dp[i] = 0))
+                fi
+            done
+        fi
+    done < "$2"
+
+    if ((part == 1)); then
+        echo "$ans1"
+    else
+        local -i ans2=0
+        for n in "${dp[@]}"; do
+            ((ans2 += n))
+        done
+        echo "$ans2"
+    fi
+    return 0
+}
+
+part1() {
+    solve 1 "$1"
+    return 0
+}
+
+part2() {
+    solve 2 "$1"
+    return 0
+}
+
+tests() {
+    # shellcheck disable=SC2034
+    {
+        sample=(
+            ".......S......."
+            "..............."
+            ".......^......."
+            "..............."
+            "......^.^......"
+            "..............."
+            ".....^.^.^....."
+            "..............."
+            "....^.^...^...."
+            "..............."
+            "...^.^...^.^..."
+            "..............."
+            "..^...^.....^.."
+            "..............."
+            ".^.^.^.^.^...^."
+            "..............."
+        )
+    }
+
+    TEST part1 sample 21
+    TEST part2 sample 40
+}
+
+source "$(dirname "$0")/aoc_main.sh"