from scipy.optimize import linprog

u,v,w,x,y = map(int,input().split())
c = [-1]*5
A = [[1,0,0,1,1],[1,1,0,0,1],[1,1,1,0,0],[0,1,1,1,0],[0,0,1,1,1]]
b = [u,v,w,x,y]
x1 = (0,None)
x2 = (0,None)
x3 = (0,None)
x4 = (0,None)
x5 = (0,None)

ans = linprog(c, A_ub= A, b_ub = b, bounds=(x1,x2,x3,x4,x5), method="simplex")
print(int(-ans.fun))