n=int(input())
for _ in range(n):
	a=input()
	while len(a)!=1:
		b=""
		for i in range(len(a)-1):
			t=ord(a[i])+ord(a[i+1])-2*ord('0')
			b+=chr(t%10+t//10+ord('0'))
		a=b
	print(a)