n = int(input())
ans = []
for i in range(n):
  s = list(input())
  while True:
    if len(s) == 1:
      ans.append(s[0])
      break
    temp = []
    for i in range(len(s)-1):
      if int(s[i]) + int(s[i+1]) >= 10:
        temp.append(int(str(int(s[i]) + int(s[i+1]))[0]) + int(str(int(s[i]) + int(s[i+1]))[1]))
      else:
        temp.append(int(s[i]) + int(s[i+1]))
    s = temp

for i in ans:
  print(i)