N = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))

ans = 0
l = 0
for r in range(1, N):
    if(A[r] - A[r-1] > abs(B[r] - B[r-1])):
        ans += r - l
    else:
        l = r

print(ans)