本帖最后由 太阳之诚 于 2015-1-25 10:13 编辑
小弟现有一题,想了很久也无果。只好请教高手的指点!
背景描述看图片,有两个问题待求解。
Question 1:Find out how many 9x9 binary matrices exist with a row sum of (1, 6, 5, 5, 4, 4, 4, 3, 9) and column sum of (6, 5, 3, 6, 6, 2, 2, 6, 5).
Question 2:For all the matrices you found in Question 1, how many of them also have a sum of (1, 1, 1, 2, 3, 4, 1, 3, 4, 5, 5, 2, 2, 2, 2, 2, 1) along the 45 degree diagonal?
多谢各位指点!
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