T = int(raw_input())
for i in range(0, T):
	S = raw_input()
	while len(S) != 1:
		newS = ''
		for i in range(0, len(S)-1):
			n = int(S[i])+int(S[i+1])
			if n >= 10: n = int(str(n)[0])+int(str(n)[1])
			newS = newS + str(n)
		S = newS
	print S