You are given an array nums that consists of non-negative integers. Let us define rev(x) as the reverse of the non-negative integer x. For example, rev(123) = 321, and rev(120) = 21. A pair of indices (i, j) is nice if it satisfies all of the following conditions:
0 <= i < j < nums.lengthnums[i] + rev(nums[j]) == nums[j] + rev(nums[i])Return the number of nice pairs of indices. Since that number can be too large, return it modulo 109 + 7.
\n
Example 1:
\n\n\nInput: nums = [42,11,1,97]\nOutput: 2\nExplanation: The two pairs are:\n - (0,3) : 42 + rev(97) = 42 + 79 = 121, 97 + rev(42) = 97 + 24 = 121.\n - (1,2) : 11 + rev(1) = 11 + 1 = 12, 1 + rev(11) = 1 + 11 = 12.\n\n\n
Example 2:
\n\n\nInput: nums = [13,10,35,24,76]\nOutput: 4\n\n\n
\n
Constraints:
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