Added PascalsTriangle algorithm using Recursion

whoisnp · abranhe · commit dc2176dea97f · 2020-10-07T22:28:13.000-04:00
diff --git a/algorithms/math/pascalsTriangle.js b/algorithms/math/pascalsTriangle.js
@@ -0,0 +1,23 @@
+function pascalTriangleRecursive(lineNumber) {
+  if (lineNumber === 0) {
+    return [1];
+  }
+
+  const currentLineSize = lineNumber + 1;
+  const previousLineSize = currentLineSize - 1;
+
+  const currentLine = [];
+
+  const previousLine = pascalTriangleRecursive(lineNumber - 1);
+
+  for (let numIndex = 0; numIndex < currentLineSize; numIndex += 1) {
+    const leftCoefficient = numIndex - 1 >= 0 ? previousLine[numIndex - 1] : 0;
+    const rightCoefficient =
+      numIndex < previousLineSize ? previousLine[numIndex] : 0;
+
+    currentLine[numIndex] = leftCoefficient + rightCoefficient;
+  }
+
+  return currentLine;
+}
+console.log(pascalTriangleRecursive(40));
