mutation.js

// define a function to perform mutation on an individual
const mutation = (individual) => {
  // iterate over the cities in the individual
  for (let i = 0; i < NUM_CITIES; i++) {
    // with probability MUTATION_RATE, swap this city with another city
    if (Math.random() < MUTATION_RATE) {
      let j = Math.floor(Math.random() * NUM_CITIES);
      let temp = individual[i];
      individual[i] = individual[j];
      individual[j] = temp;
    }
  }
  // return the mutated individual
  return individual;
};