N=int(input())
a=[0,0,0,0]
res=0
for i in range(4):
    a[i] = int(input())
for i in range(N-4):
    k=int(input())
    for j in range(i%4+1):
        if res==0:
            res=k+a[j]
        else:
            res=min(res,k+a[j])
    if k<a[i%4]:
        a[i%4]=k
print(res)