Quote:we have alot of errors in our code and don't know how to solve this
It depends when the errors occur what you need to do.
If it's when you compile your app, then each error will tell you which file and which line the error is on, as well as describing what the problem is. Read the message, look at the line of code, and try to work it out. Google the error message if you have to, that can help.
It the problems happen when you run your code, then you need to look at the error itself, and at your code while it's running - and we can't do that for you.
So, it's going to be up to you.
Fortunately, you have a tool available to you which will help you find out what is going on: the debugger. How you use it depends on your compiler system, but a quick Google for the name of your IDE and "debugger" should give you the info you need.
Put a breakpoint on the first line in the function, and run your code through the debugger. Then look at your code, and at your data and work out what should happen manually. Then single step each line checking that what you expected to happen is exactly what did. When it isn't, that's when you have a problem, and you can back-track (or run it again and look more closely) to find out why.
Sorry, but we can't do that for you - time for you to learn a new (and very, very useful) skill: debugging!