added solution for finding the smallest common number

Author: jdhrnndz

src/_Problems_/get-smallest-common-number/index.js

@@ -0,0 +1,29 @@
+// Get the common smallest number between two integer arrays
+
+const getSmallestCommonNumber = (a1, a2) => {
+  let map = {};
+  let i = 0;
+  let min;
+
+  while (a1.length > i || a2.length > i) {
+    if (i < a1.length) {
+      map[`${a1[i]}a`] = true;
+      if (map[`${a1[i]}b`] && (min > a1[i] || !min)) {
+        min = a1[i];
+      }
+    }
+
+    if (i < a2.length) {
+      map[`${a2[i]}b`] = true;
+      if (map[`${a2[i]}a`] && (min > a2[i] || !min)) {
+        min = a2[i];
+      }
+    }
+
+    i++;
+  }
+
+  return min || -1;
+};
+
+module.exports = { getSmallestCommonNumber };