Task: Question Generation
Input (English): #1 return Petro Doroshenko Hetman sign the  treaty with Sultan Mehmed IV 
#2 return the  start of the   War 
#3 return year of #1 
#4 return year of #2 
#5 return the  difference of #3 and  #4
Output (English): How many years before the start of the War did Petro Doroshenko Hetmansign the treaty with Sultan Mehmed IV?