Data update

Task/Percolation-Site-percolation/JavaScript/percolation-site-percolation.js

@@ -0,0 +1,85 @@
+class Grid {
+  constructor(rowCount, colCount, probability) {
+    this.EMPTY = " ";
+    this.FILLED = ".";
+    this.PATH = "#";
+    this.table = this.createGrid(rowCount, colCount, probability);
+  }
+
+  createGrid(rowCount, colCount, probability) {
+    const table = new Array(rowCount);
+    for (let col = 0; col < rowCount; col++) {
+      table[col] = new Array(colCount);
+      for (let row = 0; row < colCount; row++) {
+        table[col][row] = Math.random() < probability ? this.FILLED : this.EMPTY;
+      }
+    }
+    return table;
+  }
+
+  percolate() {
+    for (let x = 0; x < this.table[0].length; x++) {
+      if (this.pathExists(x, 0)) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  pathExists(x, y) {
+    if (
+      y < 0 ||
+      x < 0 ||
+      x >= this.table[0].length ||
+      this.table[y][x] !== this.FILLED
+    ) {
+      return false;
+    }
+    this.table[y][x] = this.PATH;
+    if (y === this.table.length - 1) {
+      return true;
+    }
+    return (
+      this.pathExists(x, y + 1) ||
+      this.pathExists(x + 1, y) ||
+      this.pathExists(x - 1, y) ||
+      this.pathExists(x, y - 1)
+    );
+  }
+
+  display() {
+    for (let col = 0; col < this.table.length; col++) {
+      let rowStr = "";
+      for (let row = 0; row < this.table[0].length; row++) {
+        rowStr += " " + this.table[col][row];
+      }
+      console.log(rowStr);
+    }
+    console.log();
+  }
+}
+
+function main() {
+  const rowCount = 15;
+  const colCount = 15;
+  const testCount = 1000;
+
+  const grid = new Grid(rowCount, colCount, 0.5);
+  grid.percolate();
+  grid.display();
+
+  console.log(`Proportion of ${testCount} tests that percolate through the grid:`);
+  for (let probable = 0.0; probable <= 1.0; probable += 0.1) {
+    let percolationCount = 0;
+    for (let test = 0; test < testCount; test++) {
+      const testGrid = new Grid(rowCount, colCount, probable);
+      if (testGrid.percolate()) {
+        percolationCount += 1;
+      }
+    }
+    const percolationProportion = percolationCount / testCount;
+    console.log(` p = ${probable.toFixed(1)}: ${percolationProportion.toFixed(4)}`);
+  }
+}
+
+main();