I would expect something worse than bubble sort. No idea whether it will even work: void reverse(auto A, int start, int end) { for (int i = 0; i < (end - start) / 2; i = i + 1) { auto tmp = A[start + i]; A[start + i] = A[end - i]; A[end - i] = tmp; } } for (int j = 0; j < N; j = j + 1) { for (int i = 0; i < N; i = i + 1) { if (A[i] < A[i + 1]) { reverse(A, i, N); } } }