Ternary operator precedence and assignment

Question

I have an unusual bug in my code, where sometimes, my code will return the wrong value. I have a ternary expression in a function which may be the culprit, and it's written like this;

corpusBoard[i][j] = (piece == 'o') ? 'o' : 'x';

Which should state, if piece is equal to 'o', then assign 'o' to corpusBoard[i][j], otherwise assign 'x' to corpusBoard[i][j].

Are these two statements below equivalent? If not, why?

corpusBoard[i][j] = (piece == 'o') ? 'o' : 'x';
corpusBoard[i][j] = ((piece == 'o') ? 'o' : 'x');

Edit:

The particular issue I'm having is with a project I'm working on, where the system checks a database of sorts for matches, then instantiates player pieces to characters in the database. As the pieces can be either 'o' or 'x', I wanted a simple way to "flip" them when doing a pattern match in the database:

std::vector<std::vector<char>> Machine::matchCorpus(std::vector<std::vector<char>> corpusBoard)
{
    for(int i = 0; i < corpusBoard.size(); i++){
        for(int j = 0; j < corpusBoard[0].size(); j++){
            if(corpusBoard[i][j] == 'M'){
               corpusBoard[i][j] = ((piece == 'o') ? 'x' : 'o');
            }
            if(corpusBoard[i][j] == 'H'){
                corpusBoard[i][j] = ((piece == 'o') ? 'o' : 'x');
            }

        }

    }
    return corpusBoard;
}

Unfortunately, in very rare cases, it returns the wrong value, even though if piece is 'o', and corpusBoard[i][j] == 'H', it should always assign corpusBoard[i][j] to 'o', but rarely, it gets assigned 'x' instead.

Answer 1

Yes, they are equivalent. = comes last.