你能再解释一下抽象的过程吗？ (1 for i 1 to r (2) for j 1 to m (3) S=0 (4) for k 1 to n (5) SS A[i,k]B[k,j] (6] c[i,j]S How many multiplications (expressed in terms of r,m,and n)does this pseudocode carry out in total among all the iterations of Line 5? T =USj. =∑S=∑n=mn j- i 乘法原则是否是必须明确给出的呢？你能再解释一下抽象的过程吗？ 乘法原则是否是必须明确给出的呢？