Task: Program Execution
Input (English): 1687, w, Z, 5603, N, 3423, 5059, 7673, m, f, 1591, O, 4359, U, 1253, 5019, 2473, 3523, W, o, b, 5345, 3409, 9135
Output (English): 2, 3, 5, 9, 10, 12, 14, 19, 20, 21