试试这个:

def seriesrun(x, n):
    power = 0
    s = 0

    while power < n:
        s += (-x)**power

        power +=1
    return s

试试这个:

def cv_iterative(m):    
    for i in range(1, len(m)+1):
        for j in range(1, len(m[-i])+1):

            s = m[-i][-j]

            if j != 1:
                s += m[-i][-j+1]
            if i != 1:
                s += m[-i+1][-j]

            m[-i][-j] = s

    return m

M = [[3, 0, 2, 18],[-1, 1, 3, 4],[-2, -3, 18, 7]]
CV = cv_iterative(M)
print(CV)
print(CV[0][0])

如果你只想得到 216 写 return m[0][0] 而不是 return m 然后:

M = [[3, 0, 2, 18],[-1, 1, 3, 4],[-2, -3, 18, 7]]
print(cv_iterative(M))