Feature: Jump Search

src/algorithms/searching/jumpSearch.js

@@ -0,0 +1,23 @@
+function jumpSearch(list, itemToFind, jumpSize = 4) {
+  let step = Math.floor(Math.sqrt(jumpSize));
+  let prev = 0;
+  while (list[Math.min(step, list.length) - 1] < itemToFind) {
+    prev = step;
+    step = step + jumpSize;
+    if (prev >= list.length) {
+      return false;
+    }
+  }
+  while (list[parseInt(prev)] < itemToFind) {
+    prev++;
+    if (prev == Math.min(step, list.length)) {
+      return false;
+    }
+  }
+  if (list[parseInt(prev)] === itemToFind) {
+    return true;
+  }
+  return false;
+}
+
+module.exports = jumpSearch;

test/algorithms/searching/jumpSearch.test.js

@@ -0,0 +1,40 @@
+const jumpSearch = require("../../../src/algorithms/searching/jumpSearch");
+
+describe("Jump Search algorithm", () => {
+  it("tests for item does exist", () => {
+    const arr1 = [1, 3, 5, 7, 8, 9];
+    const result = jumpSearch(arr1, 8, 7);
+    expect(result).toBe(true);
+  });
+  it("tests for item does not exist and item is less than biggest element", () => {
+    const arr1 = [1, 3, 5, 7, 8, 9];
+    const result = jumpSearch(arr1, 2);
+    expect(result).toBe(false);
+  });
+
+  it("tests for item does not exist", () => {
+    const arr1 = [1, 3, 5, 7, 8, 9];
+    const result = jumpSearch(arr1, 200, 20);
+    expect(result).toBe(false);
+  });
+  it("tests for item does exist when jumpSize is valid", () => {
+    const arr1 = [1, 3, 5, 7, 8, 9];
+    const result = jumpSearch(arr1, 8, 7, 2);
+    expect(result).toBe(true);
+  });
+  it("tests for item does not exist when jumpSize is valid", () => {
+    const arr1 = [1, 3, 5, 7, 8, 9];
+    const result = jumpSearch(arr1, 4, 1);
+    expect(result).toBe(false);
+  });
+  it("tests for item does exist when jumpSize is invalid", () => {
+    const arr1 = [1, 3, 5, 7, 8, 9, 40, 100, 200];
+    const result = jumpSearch(arr1, 100, -20);
+    expect(result).toBe(true);
+  });
+  it("tests for item does not exist when jumpSize is invalid", () => {
+    const arr1 = [1, 3, 5, 7, 8, 9, 40, 100, 200];
+    const result = jumpSearch(arr1, 300, -20);
+    expect(result).toBe(false);
+  });
+});