Merge branch 'master' of github.com:knaxus/problem-solving-javascript

Author: ashokdey

src/Searching/BinarySearch/BinarySearch.test.js

@@ -0,0 +1,41 @@
+const { binarySearch, binarySearchRecursive } = require('.');
+
+describe('Binary Search', () => {
+  const array = [1, 2, 3, 4, 5, 6, 7, 8];
+  const low = 0;
+  const high = array.length - 1;
+
+  describe('When element to find is at 1st position ', () => {
+    it('Binary search with Loop', () => {
+      expect(binarySearch(array, 1)).toEqual(0);
+    });
+    it('Binary serach with recursion', () => {
+      expect(binarySearchRecursive(array, low, high, 1)).toEqual(0);
+    });
+  });
+  describe('When element to find is at last position ', () => {
+    it('Binary search with Loop', () => {
+      expect(binarySearch(array, 7)).toEqual(6);
+    });
+    it('Binary serach with recursion', () => {
+      expect(binarySearchRecursive(array, low, high, 7)).toEqual(6);
+    });
+  });
+  describe('When element to find is at random position ', () => {
+    it('Binary search with Loop', () => {
+      expect(binarySearch(array, 3)).toEqual(2);
+    });
+    it('Binary serach with recursion', () => {
+      expect(binarySearchRecursive(array, low, high, 3)).toEqual(2);
+    });
+  });
+  describe('When element to find is no present in array ', () => {
+    it('Binary search with Loop', () => {
+      expect(binarySearch(array, 10)).toEqual(null);
+    });
+    it('Binary serach with recursion', () => {
+      expect(binarySearchRecursive(array, low, high, 10)).toEqual(null);
+    });
+  });
+  
+});

src/Searching/BinarySearch/index.js

@@ -33,3 +33,8 @@ function binarySearchRecursive(arr, low, high, key) {
     return binarySearchRecursive(arr, mid + 1, high, key);
   }
 }
+
+module.exports = {
+  binarySearch,
+  binarySearchRecursive,
+};

src/_Problems_/product-of-elements/index.js

@@ -21,9 +21,41 @@ function findProduct(arr) {
   let right = 1;
 
   // multiply all the numbers to the right side
-  for (let i = arr.length - 1; i > 0; i -= 1) {
+  for (let i = arr.length - 1; i >= 0; i -= 1) {
     result[i] *= right;
     right *= arr[i];
   }
   return result;
 }
+
+function findProduct2(arr) {
+  let countZeros = 0;
+  let positionOfZero = -1;
+  let productOffAllExpectZero = 1;
+  let result = [];
+  for (let i = 0; i < arr.length; i += 1) {
+    if (arr[i] === 0) {
+      countZeros += 1;
+      positionOfZero = i;
+    } else {
+      productOffAllExpectZero *= arr[i];
+    }
+  }
+
+  if (countZeros === 0) {
+    for (let i = 0; i < arr.length; i += 1) {
+      result[i] = productOffAllExpectZero / arr[i];
+    }
+  } else if (countZeros === 1) {
+    result = Array(arr.length).fill(0);
+    result[positionOfZero] = productOffAllExpectZero;
+  } else if (countZeros >= 2) {
+    result = Array(arr.length).fill(0);
+  }
+  return result;
+}
+
+module.exports = {
+  findProduct,
+  findProduct2,
+};

src/_Problems_/product-of-elements/product-of-elements.test.js

@@ -0,0 +1,53 @@
+const { findProduct, findProduct2 } = require('.');
+
+describe('Productof elements', () => {
+  let array = [];
+
+  describe('When count of zero is 0', () => {
+    beforeEach(() => {
+      array = [1, 2, 3, 4];
+    });
+    it('With 1st Approach', () => {
+      expect(findProduct(array)).toEqual([24, 12, 8, 6]);
+    });
+    it('With 2st Approach', () => {
+      expect(findProduct2(array)).toEqual([24, 12, 8, 6]);
+    });
+  });
+
+  describe('When count of zero is 1', () => {
+    beforeEach(() => {
+      array = [2, 3, 0, 4];
+    });
+    it('With 1st Approach', () => {
+      expect(findProduct(array)).toEqual([0, 0, 24, 0]);
+    });
+    it('With 2st Approach', () => {
+      expect(findProduct2(array)).toEqual([0, 0, 24, 0]);
+    });
+  });
+
+  describe('When count of zero is  2', () => {
+    beforeEach(() => {
+      array = [0, 3, 0, 4];
+    });
+    it('With 1st Approach', () => {
+      expect(findProduct(array)).toEqual([0, 0, 0, 0]);
+    });
+    it('With 2st Approach', () => {
+      expect(findProduct2(array)).toEqual([0, 0, 0, 0]);
+    });
+  });
+
+  describe('When count of zero is greater than  2', () => {
+    beforeEach(() => {
+      array = [0, 3, 0, 4, 8, 0];
+    });
+    it('With 1st Approach', () => {
+      expect(findProduct(array)).toEqual([0, 0, 0, 0, 0, 0]);
+    });
+    it('With 2st Approach', () => {
+      expect(findProduct2(array)).toEqual([0, 0, 0, 0, 0, 0]);
+    });
+  });
+});