Task: Program Execution
Input (English): 3, 7, ['669', '9255', 'j', 'Y', '3765', 'U', '405', 'P', 'G', '2817', 'a', 'R', '6639', '2147', '3791', 'k', '3861', 'b', '4375', '1743']
Output (English): 504U5673Yj