description: Some number of people (this number is even) have stood in a circle. The people stand in the circle evenly. They are numbered clockwise starting from a person with the number 1. Each person is looking through the circle's center at the opposite person.
  
  <image> A sample of a circle of 6 persons. The orange arrows indicate who is looking at whom.
  
  You don't know the exact number of people standing in the circle (but this number is even, no doubt). It is known that the person with the number a is looking at the person with the number b (and vice versa, of course). What is the number associated with a person being looked at by the person with the number c? If, for the specified a, b, and c, no such circle exists, output -1.
  
  Input
  
  The first line contains one integer t (1 ≤ t ≤ 10^4) — the number of test cases. Then t test cases follow.
  
  Each test case consists of one line containing three distinct integers a, b, c (1 ≤ a,b,c ≤ 10^8).
  
  Output
  
  For each test case output in a separate line a single integer d — the number of the person being looked at by the person with the number c in a circle such that the person with the number a is looking at the person with the number b. If there are multiple solutions, print any of them. Output -1 if there's no circle meeting the given conditions.
  
  Example
  
  Input
  
  
  7
  6 2 4
  2 3 1
  2 4 10
  5 3 4
  1 3 2
  2 5 4
  4 3 2
  
  
  Output
  
  
  8
  -1
  -1
  -1
  4
  1
  -1
  
  Note
  
  In the first test case, there's a desired circle of 8 people. The person with the number 6 will look at the person with the number 2 and the person with the number 8 will look at the person with the number 4.
  
  In the second test case, there's no circle meeting the conditions. If the person with the number 2 is looking at the person with the number 3, the circle consists of 2 people because these persons are neighbors. But, in this case, they must have the numbers 1 and 2, but it doesn't meet the problem's conditions.
  
  In the third test case, the only circle with the persons with the numbers 2 and 4 looking at each other consists of 4 people. Therefore, the person with the number 10 doesn't occur in the circle.
solution: """
  // Author : snape_here - Susanta Mukherjee
       
   """
  
  from __future__ import division, print_function
   
  import os,sys
  from io import BytesIO, IOBase
   
  if sys.version_info[0] < 3:
      from __builtin__ import xrange as range
      from future_builtins import ascii, filter, hex, map, oct, zip
   
  def ii(): return int(input())
  def fi(): return float(input())
  def si(): return input()
  def msi(): return map(str,input().split())
  def mi(): return map(int,input().split())
  def li(): return list(mi())
  def lsi(): return list(msi())
   
  def read():
      sys.stdin = open('input.txt', 'r')  
      sys.stdout = open('output.txt', 'w') 
   
  def gcd(x, y):
      while y:
          x, y = y, x % y
      return x
  
  def lcm(x, y):
      return (x*y)//(gcd(x,y))
  
  mod=1000000007
  
  def modInverse(b,m): 
      g = gcd(b, m)  
      if (g != 1):         
          return -1
      else:          
          return pow(b, m - 2, m) 
  
  def ceil2(x,y):
      if x%y==0:
          return x//y
      else:
          return x//y+1
  
  def modu(a,b,m): 
  
      a = a % m 
      inv = modInverse(b,m) 
      if(inv == -1): 
          return -999999999
      else: 
          return (inv*a)%m
  
  from math import log,factorial,cos,tan,sin,radians,floor,sqrt,ceil
  
  import bisect
  import random
  import string 
  import itertools
  
  from decimal import *
  
  getcontext().prec = 50
  
  abc="abcdefghijklmnopqrstuvwxyz"
  
  pi=3.141592653589793238
  
  def gcd1(a):
      if len(a) == 1:
          return a[0]
      ans = a[0]
      for i in range(1,len(a)):
          ans = gcd(ans,a[i])
      return ans
  
  def mykey(x):
      return len(x)
  
  def main():
  
      for _ in range(ii()):
          a,b,c=mi()
          if a>b:
              a,b=b,a
          mx = (b-a)*2
          if c>b:
              x = c-b
              d = a+x 
          else:
              x = c-a 
              d = b+x
              if d>mx:
                  d -= mx
          if max(a,b,c,d)>mx:
              print(-1)
              continue
          print(d)
  
  
  
  # region fastio
  
  # template taken from https://github.com/cheran-senthil/PyRival/blob/master/templates/template.py
  
  BUFSIZE = 8192
   
  
  class FastIO(IOBase):
      newlines = 0
   
      def __init__(self, file):
          self._fd = file.fileno()
          self.buffer = BytesIO()
          self.writable = "x" in file.mode or "r" not in file.mode
          self.write = self.buffer.write if self.writable else None
   
      def read(self):
          while True:
              b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
              if not b:
                  break
              ptr = self.buffer.tell()
              self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
          self.newlines = 0
          return self.buffer.read()
   
      def readline(self):
          while self.newlines == 0:
              b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
              self.newlines = b.count(b"\n") + (not b)
              ptr = self.buffer.tell()
              self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
          self.newlines -= 1
          return self.buffer.readline()
   
      def flush(self):
          if self.writable:
              os.write(self._fd, self.buffer.getvalue())
              self.buffer.truncate(0), self.buffer.seek(0)
   
   
  class IOWrapper(IOBase):
      def __init__(self, file):
          self.buffer = FastIO(file)
          self.flush = self.buffer.flush
          self.writable = self.buffer.writable
          self.write = lambda s: self.buffer.write(s.encode("ascii"))
          self.read = lambda: self.buffer.read().decode("ascii")
          self.readline = lambda: self.buffer.readline().decode("ascii")
   
   
  def print(*args, **kwargs):
      """Prints the values to a stream, or to sys.stdout by default."""
      sep, file = kwargs.pop("sep", " "), kwargs.pop("file", sys.stdout)
      at_start = True
      for x in args:
          if not at_start:
              file.write(sep)
          file.write(str(x))
          at_start = False
      file.write(kwargs.pop("end", "\n"))
      if kwargs.pop("flush", False):
          file.flush()
   
   
  if sys.version_info[0] < 3:
      sys.stdin, sys.stdout = FastIO(sys.stdin), FastIO(sys.stdout)
  else:
      sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
   
  input = lambda: sys.stdin.readline().rstrip("\r\n")
   
  # endregion
  
   
  if __name__ == "__main__":
      #read()
      main()