Final answer:
The problem of finding a subset that sums to a given number in an array is related to the subset sum issue and can be approached by dynamic programming, backtracking, and brute force strategies, while the divide and conquer approach is not suitable.
Step-by-step explanation:
The question is about finding whether a subset of an array adds up to a specific number. This problem is a classic example of the subset sum problem and can be addressed through different computational strategies. The following strategies can be applied:
- Dynamic Programming: This is an appropriate method for solving this problem. By breaking down the problem into smaller, more manageable subproblems, dynamic programming can efficiently determine if a subset adds up to the given number.
- Backtracking: Although initially stated not to be used, this is in fact a viable strategy. It involves exploring all possible subsets recursively and abandoning a branch as soon as it is clear it will not lead to the desired sum.
- Brute Force Approach: This strategy involves checking all possible combinations of the array elements to see if any add up to the given number. While not efficient for large arrays, it is a straightforward method.
- Divide and Conquer: This strategy is generally not effective for this type of problem, as dividing the array does not provide a clear path to solving the subset sum problem.
Therefore, the correct statements amongst the ones given are "Dynamic Programming: Can be used" and "Brute force Approach: Can be used". The statement "Backtracking: Cannot be used" is incorrect because backtracking is actually a valid method to address this problem. The statement "Divide and Conquer: Cannot be used" is correct, as it is generally not suitable for subset sum problems.