Algebra: December 2014

Ponturu is a japanese puzzle in which there are islands and bridges. One needs to connect islands using bridges. One can use only horizontal or vertical connections. Maximum number of bridges between two islands is two. No bridges should cross-over. The number of bridges on an island is indicated by the number inside the circle, for that island. One should make the resulting one, fully connected (there is a path from any island to any other one).

Currently, the ponturu unique solution is not guaranteed.

Get Ponturu:
Reset Ponturu:

Play FreeCell, card based game

Though it is card based game, it is not chance-based, and is entirely logical. Initially there are 8 stacks of cards, with 4 slots and 4 destinations (at the top of the board). One needs to arrange cards in the destinations using suit, "min to max card" order. One can use the slots and empty stacks as intermediate locations to keep cards. The cards in stacks, whenever you add them to stacks, should be alternate colors, "max card to min card" order.

Create a free cell puzzle:
Reset the puzzle:
Undo (one step) the puzzle:

Number Dumber is a digit arithmetic puzzle, in which one has 4 digits, and the 4 standard math operators +/-/*/// (last one is division), and a final number to make.

One has to make the final number using the 4 digits, using these 4 math ops. No brackets (grouping) allowed, and expressions are evaluated from left to right, as in 7 - 3 * 5 / 1 is evaluated as, 4 * 5 / 1 20 / 1 20

Notice that using 4 4's with math operators to generate numbers from 1 to 100, is kind of like a special application of this.

I have written a solver, that solves the NumberDumber, given the digits and the final number. The solver, as well as the puzzle creator are here. Get some puzzles and try solving them, by not using solver.

The puzzles are reasonably tough (how tough can be digit arithmetic :-)), as in they have a unique solution only.

Enter the first number:
Enter the second number:
Enter the third number:
Enter the forth number:
Enter the result number:

The result is displayed here:

Algebra

Thursday, 18 December 2014

Algebra Solver (From Wolfram Mathworld)

Get Sudoku:
Solve it:
Difficulty level:

Enter maze width here:
Enter maze height here:

Start a game:
Puzzled! Get back to original board:

Enter 4inARow width here:
Enter 4inARow height here: