Langton ant

Cellular-Automata/LangtonAnt.js

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+/**
+ * Langton's Ant
+ * Langton's Ant is a cellular automaton that involves an "ant" moving on a grid of cells.
+ * The ant changes the color of each cell it visits and turns based on the cell's color.
+ */
+
+/**
+ * Simulates Langton's Ant for a given number of steps.
+ * @param {number} steps - The number of steps to simulate.
+ */
+
+export function simulateLangtonAnt(steps, gridSize) {
+  // Initialize the grid
+  const grid = Array.from({ length: gridSize }, () =>
+    Array(gridSize).fill(false)
+  );
+
+  // Initialize the ant's position and direction
+  let antX = Math.floor(gridSize / 2);
+  let antY = Math.floor(gridSize / 2);
+  let antDirection = 'up'; // Initial direction (up, down, left, or right)
+
+  // Define the Langton's Ant rules
+  const turnRight = { up: 'right', right: 'down', down: 'left', left: 'up' };
+  const turnLeft = { up: 'left', left: 'down', down: 'right', right: 'up' };
+
+  // Simulate Langton's Ant for the specified number of steps
+  for (let step = 0; step < steps; step++) {
+    // Check the current cell's color
+    const isWhite = grid[antY][antX];
+
+    // Flip the color of the current cell
+    grid[antY][antX] = !isWhite;
+
+    // Turn the ant based on the cell's color
+    antDirection = isWhite ? turnRight[antDirection] : turnLeft[antDirection];
+
+    // Move the ant forward
+    if (antDirection === 'up') {
+      antY--;
+    } else if (antDirection === 'down') {
+      antY++;
+    } else if (antDirection === 'left') {
+      antX--;
+    } else if (antDirection === 'right') {
+      antX++;
+    }
+
+    // Handle ant's position wrapping around the grid edges
+    if (antX < 0) antX = gridSize - 1;
+    if (antX >= gridSize) antX = 0;
+    if (antY < 0) antY = gridSize - 1;
+    if (antY >= gridSize) antY = 0;
+  }
+
+  return grid;
+}

Cellular-Automata/test/LangtonAnt.test.js

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+// LangtonAnt.test.js
+import { simulateLangtonAnt } from './LangtonAnt';
+
+describe('LangtonAnt', () => {
+  it('Simulates LangtonAnt for 1 step', () => {
+    const gridSize = 11;
+    const steps = 1;
+    const result = simulateLangtonAnt(steps, gridSize);
+
+    // Add your assertions here to check the grid state after 1 step
+  });
+
+  it('Simulates LangtonAnt for 10 steps', () => {
+    const gridSize = 21;
+    const steps = 10;
+    const result = simulateLangtonAnt(steps, gridSize);
+
+    // Add your assertions here to check the grid state after 10 steps
+  });
+
+  it('Simulates LangtonAnt for 50 steps', () => {
+    const gridSize = 31;
+    const steps = 50;
+    const result = simulateLangtonAnt(steps, gridSize);
+
+    // Add your assertions here to check the grid state after 50 steps
+  });
+
+  // Add more test cases as needed to cover different scenarios
+});