я сравнил по диагонали значения двумерного массива с веерху вниз --- \, а как сравнить по диагонали снизу вверх, не могу догнать --- /?

public boolean isWinPositionForDiagonals(int[][] field, int playerToCheck) {
        int countOne =0, countTwo = 0;
        for (int i = field.lenght;i > 0; i--) {
            for (int j = 0; j < field[0].length; j++) {
                if (i == field[0].lenght - j - 1 && field[i][j] == playerToCheck) {
                    countOne++;
                } else if ((field.length - i -1) == (field[0].length - j - 1) && field[field.length - i - 1][j] == playerToCheck) {
                    countTwo++;
                }
            }
        }
        if (countOne == 3) {
            return true;
        } else if (countTwo == 3) {
            return true;
        }
        return false;
    } 

public boolean isWinPositionForDiagonals(int[][] field, int playerToCheck) {
        int countOne =0, countTwo = 0;
        for (int i = 0; i < field.length; i++) {
            for (int j = 0; j < field[0].length; j++) {
                if (i == j && field[i][j] == playerToCheck) {
                    countOne++;
                } if ((j + i + 1) == field.length && field[i][j] == playerToCheck) {
                    countTwo++;
                }
            }
        }
        if (countOne == 3) {
            return true;
        } if (countTwo == 3) {
            return true;
        }
        return false;
    }