Method isValid

Java/LeetCodeN-Queens.java:35–51

(List<String> list, int row, int column, int n)

        }
    }
    public static boolean isValid(List<String> list, int row, int column, int n){
        if(row > 0){
            String cmp = list.get(row - 1);
            for(int i = 0; i < row; i++)
                if(list.get(i).charAt(column) == 'Q') return false;
            int tempRow = row;
            int tempCol = column;
            while(--tempRow >= 0 && --tempCol >= 0){
                if(list.get(tempRow).charAt(tempCol) == 'Q') return false;
            }
            tempRow = row;
            tempCol = column;
            while(--tempRow >= 0 && ++tempCol <= n-1)
                if(list.get(tempRow).charAt(tempCol) == 'Q') return false;
        }
        return true;
    }
    private static String createQueen(int n, int index){
        StringBuilder sb = new StringBuilder();
        int i = 0;