How to find the first solution only with this backtracking

Question

i\'m trying to write a Sudoku solver which will return only the first possible solution. i managed to print all possible solutions with void methods but i can\'t stop on the

Answer 1

Change

        if(board1.boardIsOk())           // check if the board is legal
            return nextCell(line, column); // continue

into

        if(board1.boardIsOk()) {          // check if the board is legal
            boolean solved = nextCell(line, column); // continue
            if (solved) {
                return true;
            ]
        }
    ...
    return false;