Task: Program Execution
Input (English): 2379, z, 2179, 7103, r, W, G, t, z, 4547, y, 8399, x, E, Y, 4753, y, K, M, 6733, Y, B, A, 4155
Output (English): 2, 5, 6, 7, 8, 9, 11, 13, 14, 15, 17, 18, 19, 21, 22, 23