AoC-2022 Day 2b -- branchless approach

// NOTE: benchmarks show 30% pessimisation on ARMs

const char* input = R"(A Y
B X
C Z
)";


int main()
{
    int score = 0;

    bool parsingOk = true;
    int i = 0;
    while (parsingOk && input[i])
    {
        char his = '\0';
        char winType = '\0';

        his = input[i];
        i += (0 != input[i]);
        i += (0 != input[i]);
        winType = input[i];
        i += (0 != input[i]);
        i += ('\n' == input[i]);

        parsingOk &= ('A' == his) || ('B' == his) || ('C' == his);
        parsingOk &= ('X' == winType) || ('Y' == winType) || ('Z' == winType);

        // map rules
        char mine = (('X' == winType) && ('A' == his)) * 'C'    // rock beats scissors
            + (('X' == winType) && ('B' == his)) * 'A'  // paper beats rock
            + (('X' == winType) && ('C' == his)) * 'B'  // scissors beats paper
            + (('Y' == winType) && ('A' == his)) * 'A'  // par
            + (('Y' == winType) && ('B' == his)) * 'B'  // par
            + (('Y' == winType) && ('C' == his)) * 'C'  // par
            + (('Z' == winType) && ('A' == his)) * 'B'  // rock beaten by paper
            + (('Z' == winType) && ('B' == his)) * 'C'  // paper beaten by scissors
            + (('Z' == winType) && ('C' == his)) * 'A'  // scissors beaten by rock
            ;

        // calculate score
        score += mine - 'A' + 1;
        score += ('Y' == winType) * 3 + ('Z' == winType) * 6;
    }

    return score;

//    printf("%d\n", score);
//    return 0;
}