Cat Sudoku Level 77 Hint
Find a colored region with only a few safe cells, then compare those cells against the row and column limits.
Cat Sudoku Level 77 Strategy
Medium Level 77 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 77 Solution
Solution cells: R1C1, R2C4, R3C2, R4C7, R5C5, R6C3, R7C6.