algorithm: linear search (#75)

Author: vcnovaes

Search/LinearSearch.ts

@@ -0,0 +1,18 @@
+/**
+ * @function linearSearch
+ * @description linear search is the simplest search possible in a array 
+ *  it has a linear cost, if the value is present in the array, then the index of the first occurence will be returned 
+ *  if it's not present, the return it will be -1 
+ * @param {number[]} array - list of numbers
+ * @param {number} target - target number to search for
+ * @return {number} - index of the target number in the list, or -1 if not found
+ * @see https://en.wikipedia.org/wiki/Linear_search\
+ * @example linearSearch([1,2,3,5], 3) => 2
+ * @example linearSearch([1,5,6], 2) => -1
+ */
+export const linearSearch = (array: any[], target: any): number => {
+  for (let i = 0; i < array.length; i++) {
+    if (array[i] === target) return i;
+  }
+  return -1;
+}

Search/test/LinearSearch.test.ts

@@ -0,0 +1,14 @@
+import { linearSearch } from "../LinearSearch";
+
+describe("Linear search", () => {
+  test.each([
+    [['o', 'b', 'c'], 'c', 2],
+    [[1, 2, 3, 4, 5], 4, 3],
+    [['s', 't', 'r', 'i', 'n', 'g'], 'a', -1]
+  ])(
+    "of %o , searching for %o, expected %i",
+    (array: any[], target: any, index: number) => {
+      expect(linearSearch(array, target)).toStrictEqual(index)
+    },
+  );
+});