3、while九九乘法表

line = 1
while line <= 9:
    #循环体
    #内层循环：控制列
    colum = 1
    while colum <= line:
        print("%dx%d=%d"%(colum,line,line*colum),end=" ")
        colum += 1
    #换行
    print("")
    line += 1