Disjoint Groups Sudoku Puzzles (Fun With Sudoku #255 #256)

Disjoint Groups Sudoku is one of my favorite types. There was time when I used to fear this Sudoku type and was not very good in solving this Sudoku type. However with the practice I have understood techniques to solve this Sudoku type and now I can solve this Sudoku type very comfortable. However still there is lots of scope in improvement for this Sudoku type. Today I am posting two of Disjoint Groups Sudoku. First one is easy one and second one is relative tough. However both the puzzles should not take more than 5 minutes for an experience Sudoku player.
I am posting these Disjoint Groups Sudoku puzzles in Fun With Sudoku Series as 255th and 256th Sudoku puzzles in this series.

Rules of Disjoint Groups Sudoku

Disjoint Groups Sudoku Puzzle (Fun With Sudoku #255)

Disjoint Groups Sudoku Puzzle (Fun With Sudoku #255) Solution

Disjoint Groups Sudoku Puzzle (Fun With Sudoku #256)

Disjoint Groups Sudoku Puzzle (Fun With Sudoku #256) Answer

Previous Sudoku Classic Sudoku Puzzles (Fun With Sudoku #253, #254)

Next Sudoku No Touch Sudoku Puzzle (Fun With Sudoku #257)