/* #Coding challenge Given a number N create a NxN spiral matrix. function spiralMatrix(3) Output : [[1,2,3], [8,9,4], [7,6,5]] spiralMatrix(4) [[1,2,3, 4], [12,13 ,14 ,5], [11,16,15, 6], [10,9, 8, 7]] https://www.sololearn.com/post/169741/?ref=app Input: Enter a number >= 2 or press submit for default value of 8 */ #include #include #include #include // the main engine :) auto Generate_Spiral=[](auto&& mat, bool gen_reverse = false) { int const DIM(mat.at(0).size()); int num_start = gen_reverse ? ((DIM*DIM)+1): 0; int incr = gen_reverse ? -1 : 1; // navigation directions in the // matrix int const dx[] {0,1,0,-1}; int const dy[] {1,0,-1,0}; for(int row{0},col{-1},i{0},im{0}; i> DIM; if(DIM < 2) { std::cout << "Matrix dimensions must be greater or equal to 2"; return -1; } // end if(DIM < 2) // matrix storage std::vector> mat(DIM, std::vector(DIM)); // clockwise spiral Generate_Spiral(mat); std::cout << "Displaying clockwise spiral\n\n"; Print_Spiral(mat); // reverse clockwise spiral Generate_Spiral(mat, true); std::cout << "Displaying reverse clockwise spiral\n\n"; Print_Spiral(mat); return 0; }

[Challenge] Spiral Matrix.cpp