Task: Program Execution
Input (English): x, J, S, x, 3885, 309, j, U, 6767, 6915, 3845, 1989, L, 4491, p, 3529, A, B, 2635, p, t, T, l
Output (English): 1, 2, 3, 4, 7, 8, 13, 15, 17, 18, 20, 21, 22, 23