From f84cccc1b510ade19bc445249fef6dadc47a82af Mon Sep 17 00:00:00 2001
From: Imbus <imbus64@protonmail.com>
Date: Tue, 5 Dec 2023 16:13:57 +0100
Subject: [PATCH] Better comments

---
 app/src/main/java/sudoku/Solver.java | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/app/src/main/java/sudoku/Solver.java b/app/src/main/java/sudoku/Solver.java
index 1fea9c7..0d5ca47 100644
--- a/app/src/main/java/sudoku/Solver.java
+++ b/app/src/main/java/sudoku/Solver.java
@@ -38,6 +38,7 @@ public class Solver implements SudokuSolver {
             return false;
         }
 
+        // If row is 9, drop down to the next column, if column is 9, we are done
         if (row == 9) {
             row = 0;
             if (++col == 9) {
@@ -45,13 +46,17 @@ public class Solver implements SudokuSolver {
             }
         }
 
+        // If we have a "number" in the current cell
+        // recursively call solve() on the next cell
         if (board[row][col] != 0) {
             return solve(row + 1, col);
         }
 
+        // Check for legal values in the current cell
         for (int val = 1; val <= 9; ++val) {
             if (legal(row, col, val)) {
                 board[row][col] = val;
+                // When we find a legal value, recursively call solve() on the next cell
                 if (solve(row + 1, col)) {
                     return true;
                 }