Beginning in the yellow cell, create a 1-cell wide path that cannot cross itself or touch itself orthogonally, but can touch itself diagonally; the path must alternate between circles and coloured cells (beginning with yellow) until all circles and all coloured cells are taken. The grey cells are walls. The digit in a wall cell indicates the number of path cells in the 8 cells around that wall. Circle cells are different odd digits, square cells (the 4 coloured cells) are different even digits. Row 5 and Column 5 wrap around, meaning the path can pass through one end and come out on the other side (like in Pac-Man).