Hi,
1) In the PCR ZLPC we are setting the variable ZRUN to 1 if the first run is already complete.
2) In the rule ZZZ1 the line AMT=& ZRUN will copy the value of the variable ZRUN to the Amt field.
We are then comparing the value of the field with 0. The reason , because if ZRUN=0, that means this is still the first run and hence we are carrying out the specific logic required only for the first run.
If the value is not 0, that means ZRUN=1, which means that the first run is already complete and a subsequent run is being processed. This will happen only if DDNTK is not empty after the first run(there are deductions not taken and hence the system has to go into another run). (PCR ZLPC is called IF DDNT)
The processing in this case is different.