문제
import sys
input = sys.stdin.readline
N = int(input())
A = []
B = []
AB = []
BA = []
for i in range(N-1):
Ai, Bi, ABi, BAi = map(int, input().split())
A.append(Ai)
B.append(Bi)
AB.append(ABi)
BA.append(BAi)
An, Bn = map(int, input().split())
A.append(An)
B.append(Bn)
answer_A = A[:]
answer_B = B[:]
for i in range(len(A)):
if i == 0:
continue
answer_A[i] = min(answer_A[i-1]+answer_A[i], answer_A[i-1]+B[i] + AB[i-1])
answer_B[i] = min(answer_B[i-1]+answer_B[i], answer_B[i-1]+A[i] + BA[i-1])
print(min(answer_A[-1], answer_B[-1]))