动态规划算法 求4个矩阵连乘的最少量。

a1 = [

        [1,2]

    ]

a4 = [

        [2,3,4],

        [3,4,5]

    ]

a2 = [

        [4,5,6,7],

        [5,6,7,8],

        [6,7,8,9]

    ]

a3 = [

        [10,11,12,13,14,15],

        [11,12,13,14,15,16],

        [12,13,14,15,16,17],

        [13,14,15,16,17,18]

 

    ]

#123=6 134=12 146=24

def sortai():

    aa = [len(a1),len(a2),len(a3),len(a4)]

    return aa

 

def maxai():

    returnmax(len(a1[0]),len(a2[0]),len(a3[0]),len(a4[0]))

 

defmintimes(a,b,c,d,e):

    f1 = a*b*c+a*c*d+a*d*e

    f2 = a*b*c+c*d*e+a*c*e

    f3 = b*c*d+b*d*e+a*b*e

    f4 = b*c*d+a*b*d+a*d*e

    return min(f1,f2,f3,f4)

 

if __name__=='__main__':

    ss=sortai()

   print(mintimes(ss[0],ss[1],ss[2],ss[3],maxai()))