CF266C Below the Diagonal

You are given a square matrix consisting of $ n $ rows and $ n $ columns. We assume that the rows are numbered from $ 1 $ to $ n $ from top to bottom and the columns are numbered from $ 1 $ to $ n $ from left to right. Some cells ( $ n-1 $ cells in total) of the the matrix are filled with ones, the remaining cells are filled with zeros. We can apply the following operations to the matrix: 1. Swap $ i $ -th and $ j $ -th rows of the matrix; 2. Swap $ i $ -th and $ j $ -th columns of the matrix. You are asked to transform the matrix into a special form using these operations. In that special form all the ones must be in the cells that lie below the main diagonal. Cell of the matrix, which is located on the intersection of the $ i $ -th row and of the $ j $ -th column, lies below the main diagonal if $ i>j $ .

The first line contains an integer $ n $ $ (2

Print the description of your actions. These actions should transform the matrix to the described special form. In the first line you should print a non-negative integer $ m $ $ (m