thanx you for your comment.
i'm confused w how many hour to practice becouse i read the book abouth chopin
[pianist and teacher ]
and choipin recomended his student not to practiced more than 3 hour a day.
but then i got a book fron liszt where he recomended to practice until your body can not take anymore he talk abouth 8 10 14 hours .
It's too individual ... there are not strict rules ... it's not like xxx amount of time better results compared to xxx amount of time. It's very relative and can't be generalized like that
My rule of the thumb is to never spend too much time over the same thing. If you practice for a lot of time it must mean that you have a LOT OF DIFFERENT THINGS AND PIECES TO PRACTICE otherwise it's wasted time
What really matter as practiced time is concerned is how many things you practice in that amount of time not how many times you practice the same thing. Mindless repetition by itself has not the power to improve something, to make it right if it is wrong, to make it easy if it's hard and so on. What really happens that something clicks in the pianist as he/she instinctive "find the way". It should have happened way before and it came after so many practice time because of frustration and lack of results and not as a product of so much practice.
I would stick with Chopin
Chopin was notorious for pushing effortless playing and efficient technique (best expressivity with the least amount of physical effort)
When he kept saying to his students "facilement, facilmente (easily)" he showed to really understand the key of piano playing: economical motions that must look easy and natural. To play with effort and fatigue is playing with wrong technique and wrong motions.
Liszt has been brainwashed by Czerny finger-workout dogma for a while so you don't know whether you're reading from the czerny Liszt or the post-czerny Liszt
With Chopin you're more sure. He had GREAT result with his students and focused and mastered the teaching and practicing of a point which is even more important today given the number of injuried pianists, students and teacher (often to the level of giving up any performing career ... even amateurial playing) tensioless, effortless and efficient playing