from __future__ import print_function
import sys, math

def val(c,f,u):
  a, b = c - min(c, f), f - min(c, f)
  if u > b - a:
    return b + (lambda x: x//2+1 if x%2==0 and x!=0 else int(math.ceil(x/2.0)))(u - b)
  else:
    return None

s = int(sys.stdin.readline())
D = []
n = 0

for d,c,f,u in ( map(int, line.split()) for line in sys.stdin ):
  n += d; x = val(c,f,u)
  if x is not None: D.append((d,x))

# print(D)

m     = n//2+1
C     = [ [0,set()] for i in xrange(n+1) ]

for i in xrange(n+1):
  xs = [ (C[i-D[j][0]], j, D[j][1]) for j in xrange(len(D)) 
           if D[j][0] <= i and j not in C[i-D[j][0]][1] ]
  # print("i = ", i, " xs = ", xs)
  if xs:
    c, j, cost = min(xs, key = lambda x: x[2])
    C[i] = c[:]
    C[i][0] += cost
    C[i][1] = C[i][1].copy(); C[i][1].add(j)
  else:
    C[i] = C[i-1]
  # print(C[i])

# print(m, n)
# for c in C: print(c)

for i in xrange(n+1):
  cost, delegates = sum( D[j][1] for j in C[i][1] ), sum( D[j][0] for j in C[i][1] )
  if delegates >= m:
    print(cost)
    sys.exit(0)
print("impossible")