twinGap = 0 // current gap between twins
count = 0
maxTwinGap = 0 // max gap between twins

// while loop goes through all entries of list twins
while count < len(twins):

	// gap between twins is the list entry of index count + 1 (a tuple)
	// the [1] selects the second entry in the tuple
	twinGap = twins[count+1][1] - nextP

	// if the current twinGap is > maxTwinGap, we have a new maxTwinGap
	if twinGap > maxTwinGap:
		maxTwinGap = twinGap

	// loop update condition
	count +=1

print twinGap