+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
|     |     "     "     |     |     "     |     |     "     |     |     |
|  1  |     "     "  6  |  9  |     "     |     |     "     |  5  |  2  |
|     |     "     "     |     |     "     |     |     "     |     |     |
+=====+=====+     +-----+-----+-----+-----+-----+-----+-----+-----+-----+
|     |     "     "     |     |     "     |     |     "     |     |     |
|  6  |     " -   "  7  |     |     "     |     |     "     |     |  4  |
|     |     "     "     |     |     "     |     |     "     |     |     |
+=====+=====+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
|     |     "     "     |     |     "     |     |     "     |     |     |
|  6  |     " -   "     |     |  1  "  3  |  5  |  7  "  9  |     |     |
|     |     "     "     |     |     "     |     |     "     |     |     |
+=====+=====+=====+=====+=====+=====+=====+=====+=====+=====+=====+=====+
|     |     |     "     |     |     "     |     |     "     |     |     |
|  4  |  3  |     "     |     |  4  "     |  1  |     "  8  |     |     |
|     |     |     "     |     |     "     |     |     "     |     |     |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
|     |     |     "     |     |     "     |     |     "     |     |     |
|  1  |     |     "     |     |  5  "     |  3  |  2  "  6  |     |     |
|     |     |     "     |     |     "     |     |     "     |     |     |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
|     |     |     "     |     |     "     |     |     "     |     |     |
|     |     |  7  "     |     |     "     |     |     "  2  |     |     |
|     |     |     "     |     |     "     |     |     "     |     |     |
+=====+=====+=====+=====+=====+=====+=====+=====+=====+=====+=====+=====+
|     |     |     "     |     |     "     |     |     "     |     |     |
|     |     |  8  "     |     |  4  "  9  |     |     "  5  |     |     |
|     |     |     "     |     |     "     |     |     "     |     |     |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
|     |     |     "     |     |     "     |     |     "     |     |     |
|     |     |  9  "  8  |     |     "  1  |     |     "     |     |  6  |
|     |     |     "     |     |     "     |     |     "     |     |     |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
|     |     |     "     |     |     "     |     |     "     |     |     |
|     |     |  4  "     |  2  |     "  6  |     |     "     |  2  |  9  |
|     |     |     "     |     |     "     |     |     "     |     |     |
+=====+=====+=====+=====+=====+=====+=====+=====+=====+=====+=====+=====+
|     |     |     "     |     |     "     |     |     "     "     |     |
|     |     |  2  "  7  |  5  |  3  "  4  |     |     "     "     |  2  |
|     |     |     "     |     |     "     |     |     "     "     |     |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+     +=====+=====+
|     |     |     "     |     |     "     |     |     "     "     |     |
|  5  |     |     "     |     |     "     |     |  3  " -   "     |  9  |
|     |     |     "     |     |     "     |     |     "     "     |     |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+=====+=====+
|     |     |     "     |     |     "     |     |     "     "     |     |
|  6  |  7  |     "     |     |     "     |  8  |  5  " -   "     |  9  |
|     |     |     "     |     |     "     |     |     "     "     |     |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+