1 files changed, 9 insertions, 3 deletions
diff --git a/c/sudoku.c b/c/sudoku.c
index 3d5b2d9..8d36d92 100644
--- a/c/sudoku.c
+++ b/c/sudoku.c
@@ -8,11 +8,13 @@ char PUZZLE[81];
 
 bool inBox(int i, int n)
 {
+  int inum = n + '0';
   int boxRow = (i / 9 / 3) * 27;
   int boxCol = ((i % 9) / 3) * 3;
+
   for(int j = boxRow; j < boxRow + 27; j += 9) {
     for(int k = boxCol; k < boxCol + 3; k++){
-      if(PUZZLE[j + k] - '0' == n && i != j + k)
+      if(PUZZLE[j + k] == inum && i != j + k)
         return true;
     }
   }
@@ -22,9 +24,11 @@ bool inBox(int i, int n)
 
 bool inCol(int i, int n)
 {
+  int inum = n + '0';
   int col = i % 9;
+
   for(int j = col; j < 81; j += 9) {
-    if(PUZZLE[j] - '0' == n && i != j )
+    if(PUZZLE[j] == inum && i != j )
       return true;
   }
   return false;
@@ -33,9 +37,11 @@ bool inCol(int i, int n)
 
 bool inRow(int i, int n)
 {
+  int inum = n + '0';
   int row = (i/9) * 9;
+
   for(int j = row; j < row + 9; j++) {
-    if(PUZZLE[j] - '0' == n && i != j)
+    if(PUZZLE[j] == inum && i != j)
       return true;
   }
   return false;