Solve the standard basis pursuit program using a primal-dual algorithm,The key code of GBP is provided by Justin Romberg Reference: E. Candes and J. Romberg, “l1-Magic: Recovery of Sparse Signals via Convex Programming,” 2005.

输出9*9口诀1.程序分析：分行与列考虑，共9行9列，i控制行，j控制列。 2.程序源代码： -The output of 9*9 formulas 1 program analysis: branch and column considered, a total of 9 lines 9, I control line, J control column. 2 program source code:

题目：要求输出国际象棋棋盘。 1.程序分析：用i控制行，j来控制列，根据i+j的和的变化来控制输出黑方格，还是白方格。 -Title: requirements for the output of the chess board. 1 program analysis: using I control line, j to control the column, according to the i+j and the change to control the output of