Given an encoded string, you have to output the decoded string. The encoded string will have the following format: 1[ac2[de]], 2[a2[b3]], 3[a3[b23c1[d]k2[x]]]. Basically, a string consists of alphabets, numbers, and square brackets. Before each square bracket, there will be a sequence of numbers. The sequence of numbers represents how many times they have to be repeated in the resultant string. See example for better understanding\n\nInput: 1[ac2[de]]\nOutput: acdede\nExplanation: 2[de] means "de" should be\nrepeated two times and 1[ac....] means \nwhatever was the resultant string between\n the square brackets should be repeated only once.\n\nInput: 2[a4[b]c13d2[e]]\nOutput: abbbbc13deeabbbbc13dee\nExplanation: As you can see, the decoded\nstring may also contain digits because those digits\nare not followed by a square bracket in the encoded string.\n\nInput: 1[a2[b1[c11[d]]]]\nOutput: abcdddddddddddbcddddddddddd\nExplaination: This example shows that there\ncan be multiple digits before a square bracket(11 in\nthis case)

Given an encoded string, you have to output the decoded string. The encoded string will have the following format: 1[ac2[de]], 2[a2[b3]], 3[a3[b23c1[d]k2[x]]]. 