Cat Sudoku Level 91 Hint
Find a colored region with only a few safe cells, then compare those cells against the row and column limits.
Cat Sudoku Level 91 Strategy
Medium Level 91 uses a 7x7 board with 7 colored regions. It starts with 1 fixed cats to anchor the solve. Work from the tightest rows and regions before placing a cat.
Cat Sudoku Level 91 Solution
Solution cells: R1C4, R2C1, R3C5, R4C2, R5C7, R6C3, R7C6.