3749. Evaluate Valid Expressions

You are given a string expression that represents a nested mathematical expression in a simplified form.

A valid expression is either an integer literal or follows the format op(a,b), where:

• op is one of "add", "sub", "mul", or "div".
• a and b are each valid expressions.

The operations are defined as follows:

• add(a,b) = a + b
• sub(a,b) = a - b
• mul(a,b) = a * b
• div(a,b) = a / b

Return an integer representing the result after fully evaluating the expression.

3748. Count Stable Subarrays

You are given an integer array nums.

A subarray of nums is called stable if it contains no inversions, i.e., there is no pair of indices i < j such that nums[i] > nums[j].

You are also given a 2D integer array queries of length q, where each queries[i] = [li, ri] represents a query. For each query [li, ri], compute the number of stable subarrays that lie entirely within the segment nums[li..ri].

Return an integer array ans of length q, where ans[i] is the answer to the ith query.

Note:

• A single element subarray is considered stable.

3747. Count Distinct Integers After Removing Zeros

You are given a positive integer n.

For every integer x from 1 to n, we write down the integer obtained by removing all zeros from the decimal representation of x.

Return an integer denoting the number of distinct integers written down.

3746. Minimum String Length After Balanced Removals

You are given a string s consisting only of the characters 'a' and 'b'.

You are allowed to repeatedly remove any substring where the number of 'a' characters is equal to the number of 'b' characters. After each removal, the remaining parts of the string are concatenated together without gaps.

Return an integer denoting the minimum possible length of the string after performing any number of such operations.

3745. Maximize Expression of Three Elements

You are given an integer array nums.

Choose three elements a, b, and c from nums at distinct indices such that the value of the expression a + b - c is maximized.

Return an integer denoting the maximum possible value of this expression.

3743. Maximize Cyclic Partition Score

You are given a cyclic array nums and an integer k.

Partition nums into at most k subarrays. As nums is cyclic, these subarrays may wrap around from the end of the array back to the beginning.

The range of a subarray is the difference between its maximum and minimum values. The score of a partition is the sum of subarray ranges.

Return the maximum possible score among all cyclic partitions.

3742. Maximum Path Score in a Grid

You are given an m x n grid where each cell contains one of the values 0, 1, or 2. You are also given an integer k.

You start from the top-left corner (0, 0) and want to reach the bottom-right corner (m - 1, n - 1) by moving only right or down.

Each cell contributes a specific score and incurs an associated cost, according to their cell values:

• 0: adds 0 to your score and costs 0.
• 1: adds 1 to your score and costs 1.
• 2: adds 2 to your score and costs 1.

Return the maximum score achievable without exceeding a total cost of k, or -1 if no valid path exists.

Note: If you reach the last cell but the total cost exceeds k, the path is invalid.

3741. Minimum Distance Between Three Equal Elements II

You are given an integer array nums.

A tuple (i, j, k) of 3 distinct indices is good if nums[i] == nums[j] == nums[k].

The distance of a good tuple is abs(i - j) + abs(j - k) + abs(k - i), where abs(x) denotes the absolute value of x.

Return an integer denoting the minimum possible distance of a good tuple. If no good tuples exist, return -1.

3740. Minimum Distance Between Three Equal Elements I

You are given an integer array nums.

A tuple (i, j, k) of 3 distinct indices is good if nums[i] == nums[j] == nums[k].

The distance of a good tuple is abs(i - j) + abs(j - k) + abs(k - i), where abs(x) denotes the absolute value of x.

Return an integer denoting the minimum possible distance of a good tuple. If no good tuples exist, return -1.

3739. Count Subarrays With Majority Element II

You are given an integer array nums and an integer target.

Return the number of subarrays of nums in which target is the majority element.

The majority element of a subarray is the element that appears strictly more than half of the times in that subarray.