reorg and add code for second edition

11_dynamic_programming/javascript/examples/base.js

@@ -0,0 +1,7 @@
+module.exports = function initialize_matrix(rows, cols) {
+  let matrix = [];
+  for (let i = 0; i < rows.length; i++) {
+    matrix.push(Array(cols.length).fill(0));
+  }
+  return matrix;
+};

11_dynamic_programming/javascript/examples/diff_two_words.js

@@ -0,0 +1,25 @@
+const initialize_matrix = require("./base.js");
+
+function diff(firstWord, secondWord) {
+  let arr1 = firstWord.split("");
+  let arr2 = secondWord.split("");
+  let matrix = initialize_matrix(arr1, arr2);
+  for (let i = 0; i < arr1.length; i++) {
+    for (let j = 0; j < arr2.length; j++) {
+      if (arr1[i] == arr2[j]) {
+        if (i > 0 && j > 0) {
+          matrix[i][j] = matrix[i - 1][j - 1] + 1;
+        } else {
+          matrix[i][j] = 1;
+        }
+      } else {
+        if (i > 0 && j > 0) {
+          matrix[i][j] = Math.max(matrix[i - 1][j], matrix[i][j - 1]);
+        } else {
+          matrix[i][j] = 0;
+        }
+      }
+    }
+  }
+  return matrix[arr1.length - 1][arr2.length - 1];
+}