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Array manipulation involves modifying, adding, or removing elements in an array to structure data effectively. It’s essential for optimizing code performance, especially with large datasets. Techniques like slicing and mapping are widely used in programming. Learn more about related topics like how to activate Glo SIM.

This is my elegant solution in java with 1-indexed lists:

public static long arrayManipulation(int n, List<List<Integer>> queries) {
        // 1-indexed array
        List<Long> arr = new ArrayList<>() {
            {
                add(Long.MIN_VALUE);
                addAll(Collections.nCopies(n, 0L));
            }
        };
        for (List<Integer> query : queries) {
            Integer a = query.get(0);
            Integer b = query.get(1);
            Integer k = query.get(2);
            arr.set(a, arr.get(a) + k);
            if(b < n) {
                arr.set(b + 1, arr.get(b + 1) - k);
            }
        }
        long answer = 0, sum = 0;
        for(int i = 1; i <= n; i++) {
            sum += arr.get(i);
            answer = Math.max(answer, sum);
        }
        return answer;
    }

Hi, I've seen many use the prefix sum algorithm to solve this problem, before looking into it I was trying with this:

    arr = [0] * n
    for start, end, value in queries:
        sub_arr = arr[start - 1:end]
        add_arr = [value] * len(sub_arr)
        sub_arr = [a+b for a,b in zip(sub_arr, add_arr)]
        arr = arr[0:start - 1] + sub_arr + arr[end:]
    return max(arr)

but it says the max number is not the expected one, at the end, seems like with sum prefix we can recreate the same array I generate each query so I cannot see why the returned max value is not correct, if anyone has an answer, I would be glad to reaad i it, thanks.

Python Code Implementation Difference Array Instead Brute-Force Method

`

def arrayManipulation(n, queries): arr = [0] * (n + 1)
for a, b, k in queries: arr[a - 1] += k if b < n: arr[b] -= k max_value = 0 current_value = 0 for i in range(n): current_value += arr[i] if current_value > max_value: max_value = current_value

return max_value

fptr.write(str(result) + '\n')
fptr.close()

`