new_contents: from sys import stdin, stdout
  I = list(map(int, stdin.read().split()))
  
  primes = [2]
  maxP = 1000001
  isP = [True] * maxP
  isP[0] = isP[1] = False
  for i in range(3, maxP, 2):
    if isP[i]:
      primes.append(i)
      for j in range(i*i, maxP, i):
        isP[j] = False
  
  for c in range(0, I[0]):
    [L, R] = I[2*c+1: 2*c+3]
  
    l = -1
    F = {}
    mx = 0
    mxi = -1
    isc = False
    for i, p in enumerate(primes):
      if p > R: break
      if p < L: continue
      if l != -1:
        dif = p - l
        if not dif in F:
          F[dif] = 1
        else:
          F[dif] += 1
  
        if F[dif] > mx:
          mx = F[dif]
          mxi = dif
          isc = True
        elif F[dif] == mx and dif != mxi:
          isc = False
      l = p
  
    if isc: stdout.write('The jumping champion is {}\n'.format(mxi))
    else: stdout.write('No jumping champion\n')
  
  
subject: solve 914