Task: Program Execution
Input (English): i, a, 7297, 2521, i, 9247, c, c, 5817, 3691, 4995, 4811, s, 6209, 9431, 7351, 8539, 3185, c, 2449, j, 7655, f, s
Output (English): a, c, f, i, j, s