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class Solution {
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  public List<String> removeComments(String[] source) {
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    boolean blockActive =
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        false; // We keep track of whether or not we are within a block comment with the blockActive
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    // variable.
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    // It is initally set to false since we haven't read anything until now.
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    List<String> result = new ArrayList<String>();
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    StringBuilder builder = new StringBuilder();
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    // Read every line from the source input.
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    for (String line : source) {
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      // Each time we move on to reading a new line, we check if it is a part of a block comment.
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      // If it is already part of a block comment, it means we should skip the implicit newline
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      // characters as mentioned in the problem description.
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      // For example if Line 1 was  "int a /*Block comment Started" and Line 2 was "Block comment
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      // ends here */ b;", and Line 3 was "int c;"
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      // we want our output to be "int ab", "int c" instead of "int a", "b;", "int c;"
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      if (!blockActive) {
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        builder = new StringBuilder();
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      }
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      for (int i = 0; i < line.length(); i++) { // Read every character of line
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        char c = line.charAt(i);
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        if (!blockActive) { // If we aren't currently in a block
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          if (c == '/') { // We check if we encounter the start of a regular comment
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            // If so, then we need to check if the next character makes it a regular comment, a
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            // block comment, or neither of those two.
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            if (i < line.length() - 1
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                && line.charAt(i + 1) == '/') { // Checking if it's a regular comment
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              break; // If it's a regular comment, we can simply skip everything else
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              // until the end of the line, so we break from the loop and move on to the next line.
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            } else if (i < line.length() - 1 && line.charAt(i + 1) == '*') { // Or a block comment
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              i++; // Since we verified it's a block comment, we simply increment i so that we don't
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              // re-read the '*' again,
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              // and mark that we are now part of a block comment.
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              blockActive = true;
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            } else { // If the second character is neither a / or *, it indicates that a first
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              // character must be a valid operator
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              // (probably a mathematical operator such as multiplication or division, and not part
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              // of any comment,
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              // so simply append it to the builder)
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              builder.append(c);
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            }
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          } else { // Append all other characters directly to the builder.
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            builder.append(c);
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          }
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        } else {
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          // We skip all other characters in a block comment, and check for the closing block
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          // comment.
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          // Once we find it, we mark the blockActive variable as false to indicate that it isn't
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          // part of the block anymore.
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          if (c == '*') {
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            if (i < line.length() - 1 && line.charAt(i + 1) == '/') {
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              blockActive = false;
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              i++;
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            }
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          }
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        }
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      }
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      // We append to the result when we aren't part of a block any more, and the builder contains 1
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      // or more characters.
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      if (!blockActive && builder.length() != 0) {
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        result.add(builder.toString());
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      }
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    }
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    return result;
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  }
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}