Duplicate steps in Activity Diagram

[santoshkumar savadatti]

I need to create an Activity Diagram for the following scenario:
There's a condition x and there are 3 steps a,b&c. The system checks if "x" succeeded or failed. a&b are available regardless of whether x was success or failure.step c is available only if x succeeded.
I'm really confused about this.

[Mohamed Sanaulla]

What is confusing here?
a and b happen, then based on x, if x is succeeded then c else end.

[santoshkumar savadatti]

It is not a&b or c.
If x fails, only a&b.
If x succeeds, then a,b and c.

[Mohamed Sanaulla]

What is common between the two? Steps a and b - so they occur no matter what the value of x is, but the step c is dependent on the value of x.

[santoshkumar savadatti]

Nothing common between a &b.
C depends on the outcome of X.

[Mohamed Sanaulla]

I was asking what is common between the two:

If x fails, only a&b.
If x succeeds, then a,b and c.

and not between Step a and b.