You are given a 0-indexed integer array nums.
The concatenation of two numbers is the number formed by concatenating their numerals.
\n\n15, 49 is 1549.The concatenation value of nums is initially equal to 0. Perform this operation until nums becomes empty:
nums, pick the first element and last element in nums respectively and add the value of their concatenation to the concatenation value of nums, then delete the first and last element from nums.nums, then delete it.Return the concatenation value of the nums.
\n
Example 1:
\n\n\nInput: nums = [7,52,2,4]\nOutput: 596\nExplanation: Before performing any operation, nums is [7,52,2,4] and concatenation value is 0.\n - In the first operation:\nWe pick the first element, 7, and the last element, 4.\nTheir concatenation is 74, and we add it to the concatenation value, so it becomes equal to 74.\nThen we delete them from nums, so nums becomes equal to [52,2].\n - In the second operation:\nWe pick the first element, 52, and the last element, 2.\nTheir concatenation is 522, and we add it to the concatenation value, so it becomes equal to 596.\nThen we delete them from the nums, so nums becomes empty.\nSince the concatenation value is 596 so the answer is 596.\n\n\n
Example 2:
\n\n\nInput: nums = [5,14,13,8,12]\nOutput: 673\nExplanation: Before performing any operation, nums is [5,14,13,8,12] and concatenation value is 0.\n - In the first operation:\nWe pick the first element, 5, and the last element, 12.\nTheir concatenation is 512, and we add it to the concatenation value, so it becomes equal to 512.\nThen we delete them from the nums, so nums becomes equal to [14,13,8].\n - In the second operation:\nWe pick the first element, 14, and the last element, 8.\nTheir concatenation is 148, and we add it to the concatenation value, so it becomes equal to 660.\nThen we delete them from the nums, so nums becomes equal to [13].\n - In the third operation:\nnums has only one element, so we pick 13 and add it to the concatenation value, so it becomes equal to 673.\nThen we delete it from nums, so nums become empty.\nSince the concatenation value is 673 so the answer is 673.\n\n\n
\n
Constraints:
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