3704. Count No-Zero Pairs That Sum to N

A no-zero integer is a positive integer that does not contain the digit 0 in its decimal representation.

Given an integer n, count the number of pairs (a, b) where:

• a and b are no-zero integers.
• a + b = n

Return an integer denoting the number of such pairs.

3703. Remove K-Balanced Substrings

You are given a string s consisting of '(' and ')', and an integer k.

A string is k-balanced if it is exactly k consecutive '(' followed by k consecutive ')', i.e., '(' * k + ')' * k.

For example, if k = 3, k-balanced is "((()))".

You must repeatedly remove all non-overlapping k-balanced substrings from s, and then join the remaining parts. Continue this process until no k-balanced substring exists.

Return the final string after all possible removals.

3702. Longest Subsequence With Non-Zero Bitwise XOR

You are given an integer array nums.

Return the length of the longest subsequence in nums whose bitwise XOR is non-zero. If no such subsequence exists, return 0.

3701. Compute Alternating Sum

You are given an integer array nums.

The alternating sum of nums is the value obtained by adding elements at even indices and subtracting elements at odd indices. That is, nums[0] - nums[1] + nums[2] - nums[3]...

Return an integer denoting the alternating sum of nums.

3700. Number of ZigZag Arrays II

You are given three integers n, l, and r.

A ZigZag array of length n is defined as follows:

• Each element lies in the range [l, r].
• No two adjacent elements are equal.
• No three consecutive elements form a strictly increasing or strictly decreasing sequence.

Return the total number of valid ZigZag arrays.

Since the answer may be large, return it modulo 109 + 7.

A sequence is said to be strictly increasing if each element is strictly greater than its previous one (if exists).

A sequence is said to be strictly decreasing if each element is strictly smaller than its previous one (if exists).

3699. Number of ZigZag Arrays I

You are given three integers n, l, and r.

A ZigZag array of length n is defined as follows:

• Each element lies in the range [l, r].
• No two adjacent elements are equal.
• No three consecutive elements form a strictly increasing or strictly decreasing sequence.

Return the total number of valid ZigZag arrays.

Since the answer may be large, return it modulo 109 + 7.

A sequence is said to be strictly increasing if each element is strictly greater than its previous one (if exists).

A sequence is said to be strictly decreasing if each element is strictly smaller than its previous one (if exists).

3698. Split Array With Minimum Difference

You are given an integer array nums.

Split the array into exactly two subarrays, left and right, such that left is strictly increasing and right is strictly decreasing.

Return the minimum possible absolute difference between the sums of left and right. If no valid split exists, return -1.

3697. Compute Decimal Representation

You are given a positive integer n.

A positive integer is a base-10 component if it is the product of a single digit from 1 to 9 and a non-negative power of 10. For example, 500, 30, and 7 are base-10 components, while 537, 102, and 11 are not.

Express n as a sum of only base-10 components, using the fewest base-10 components possible.

Return an array containing these base-10 components in descending order.

3695. Maximize Alternating Sum Using Swaps

You are given an integer array nums.

You want to maximize the alternating sum of nums, which is defined as the value obtained by adding elements at even indices and subtracting elements at odd indices. That is, nums[0] - nums[1] + nums[2] - nums[3]...

You are also given a 2D integer array swaps where swaps[i] = [pi, qi]. For each pair [pi, qi] in swaps, you are allowed to swap the elements at indices pi and qi. These swaps can be performed any number of times and in any order.

Return the maximum possible alternating sum of nums.

3694. Distinct Points Reachable After Substring Removal

You are given a string s consisting of characters 'U', 'D', 'L', and 'R', representing moves on an infinite 2D Cartesian grid.

• 'U': Move from (x, y) to (x, y + 1).
• 'D': Move from (x, y) to (x, y - 1).
• 'L': Move from (x, y) to (x - 1, y).
• 'R': Move from (x, y) to (x + 1, y).

You are also given a positive integer k.

You must choose and remove exactly one contiguous substring of length k from s. Then, start from coordinate (0, 0) and perform the remaining moves in order.

Return an integer denoting the number of distinct final coordinates reachable.