/* [Challenge] Zigzag Square Pattern Lv.1: Input size and get the pattern. Lv.2: Generate from size 1 to N Lv.3: Start with downwards | 1 3 | | 2 4 | Lv.4: Start from right-top, right-bottom or left-bottom Lv.5: Display 4 (or 8) patterns from Lv.4 together | 1 2 3 1 | | 3 4 4 2 | | | | 2 4 4 3 | | 1 3 2 1 | P.S. Picture is a sample for Lv.2 */ #include #include #include using namespace std; using Va = valarray; auto fwd_fill = [](size_t const sz, size_t& curr,int dir=1) { Va lst(sz); for(size_t i{0}; i < sz; lst[i] = curr, ++i, curr += dir); return lst; }; auto rev_fill = [](size_t const sz, size_t& curr, int dir=1) { Va lst(sz); for(size_t i{sz}; i>0; lst[i-1] = curr, --i, curr += dir); return lst; }; auto print = [](auto&& mat,size_t const dim) { cout << "num = " << dim << ":\n"; for(size_t i{0}; i < dim; ++i) { for(size_t j{0}; j < dim; ++j) cout << setw(dim<=10?3:4) << right<< mat[i * dim + j]; cout << '\n'; } cout << "\n\n"; }; auto draw_pattern = [](size_t dim) { Va mat(dim * dim); mat[0] = 1; mat [dim * dim - 1]= dim * dim; // fill upper left diagonal triangle size_t curr{2}; for(size_t d{1}; d < dim; ++d) { auto slc = slice(d, d + 1, dim - 1); mat[slc] = (d & 1) ? fwd_fill(d + 1, curr): rev_fill(d + 1, curr); } // fill lower right diagonal triangle curr = dim * dim - 1; size_t s { curr }; for(size_t d{1}; d <= dim - 1; ++d) { auto slc=slice(s - d, d + 1, 1 - dim); mat[slc] = d & 1 ? fwd_fill(d + 1, curr, -1): rev_fill(d + 1, curr, -1); } print(mat, dim); }; int main() { size_t dim{4}; cin >> dim; draw_pattern(dim); for(size_t dim{2}; dim <= 10; ++dim) draw_pattern(dim); }

[Challenge] Zigzag_pattern.cpp