Skip Processing Elements Marked with -1

In certain algorithms, it may be useful to skip processing elements that have been marked with a special value, such as -1. Marking elements this way serves as a flag, indicating that the element should be ignored in subsequent operations. Skipping these marked elements can enhance efficiency, especially when the array is large.

Example Code

Java

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public class Main {
  public static void main(String[] args) {
    int[] array = {1, -1, 3, -1, 5};

    for (int i = 0; i < array.length; i++) {
      if (array[i] == -1) {
        continue;
      }
      System.out.println("Processing element: " + array[i]);
    }
  }
}

C++

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#include <iostream>
using namespace std;

int main() {
  int array[] = {1, -1, 3, -1, 5};
  int length = sizeof(array) / sizeof(array[0]);
  
  for (int i = 0; i < length; i++) {
    if (array[i] == -1) {
      continue;
    }
    cout << "Processing element: " << array[i] << endl;
  }
  
  return 0;
}

Python

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array = [1, -1, 3, -1, 5]

for num in array:
    if num == -1:
        continue
    print(f"Processing element: {num}")

Key Takeaways

Elements marked with -1 serve as flags to skip processing.
The continue statement is used to skip the current iteration of the loop, ignoring elements marked with -1.
By skipping marked elements, computational resources are saved, making the algorithm more efficient.