NumbersAndLetters

This was an exercise to my university class

This program solves numbers and letters riddle. (For example, SEND+MORE=MONEY, a solution is: 9567+1085=10652)

How to run

Compile the java files and run MMN12

The equations are solved using genetic algorithms

The equations solved can have addition, subtraction and multiplaction (no division at the moment)

The algorithm

I assume you know how genetic algorithms work, so I will just touch some important details:

• Parents are selected using classic roulette, while the most weak member is never selected
• When creating new offsprings or performing mutations, several validations are done to ensure that new members are valid
• The best member is always kept for the next generation

Avoiding early convergence

Since early ocnvergence is highly likely in this case, we use:

• Niches (sub populations) are used to avoid quick convergence and to keep the population varied
• High mutation chances
• Population restart when early convergence is detected

Evaluation function

The evaluation function is the difference between the result of the left side of the equations and the translation of the right side. Meaning, a solution to the equation has a value of 0