Killer Sudoku

Time to defeat the killer, sudoku geniuses. Same as the classic version of the number puzzle, you will be given a 9x9 grid, which is evenly divided into 9 squares. Your goal in the game is to put numbers 1 to 9 onto the blanks of the grid, such that the numbers will not be repeated in each row, each column, and each 3x3 square. In addition to that, the blanks will be separated into groups by red lines which are called cages. In each of the cages you will be given a number, and the sum of the numbers in the cage must be equal to that given number. When you hover your mouse over the given number, the possible sums will be shown for your reference. You can click a number on the number pad on the left of the grid to fill in a blank. If you would like to remove a number previously entered, you can click the cross button at the bottom of the number pad to erase it. If you are not able to put a number, you may click the Hint button under the grid to reveal one of the answers, but note that for each hint you receive 100 seconds will be added to the time you have spent, as indicated at the bottom left corner of the screen. Rise to the indulging arithmetic game now.