代码如下:
n = 5 matrix1 = [ [1] * 3 for q in range(n)] print(matrix1) for q in range(n): matrix2 = [ [2] * q] print(matrix2) >>> [[1, 1, 1], [1, 1, 1], [1, 1, 1], [1, 1, 1], [1, 1, 1]] [[]] [[2]] [[2, 2]] [[2, 2, 2]] [[2, 2, 2, 2]]
n = 5 matrix1 = [ [1] * n for q in range(n)] print(matrix1) for q in range(n): matrix2 = [ [2] * n] print(matrix2) >>> [[1, 1, 1, 1, 1], [1, 1, 1, 1, 1], [1, 1, 1, 1, 1], [1, 1, 1, 1, 1], [1, 1, 1, 1, 1]] [[2, 2, 2, 2, 2]] [[2, 2, 2, 2, 2]] [[2, 2, 2, 2, 2]] [[2, 2, 2, 2, 2]] [[2, 2, 2, 2, 2]]
关于代码的理解:
第一个for循环是在列表内部重复执行5次的结果,生成matrix1;
第二个for循环是matrix2赋值这件事情执行了5次.
注:[[ ]] 表示 列表嵌套。
参考网址:https://www.runoob.com/python3/python3-list.html