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Capril1042 · Capril1042 · commit 45b8eeacc350 · 2017-11-08T11:29:37.000-05:00
diff --git a/src/arrays.js b/src/arrays.js
@@ -9,29 +9,58 @@ const each = (elements, cb) => {
   // This only needs to work with arrays.
   // You should also pass the index into `cb` as the second argument
   // based off http://underscorejs.org/#each
+  for (let i = 0; i < elements.length; i++) {
+    cb(elements[i], i);
+  }
 };
 
 const map = (elements, cb) => {
   // Produces a new array of values by mapping each value in list through a transformation function (iteratee).
   // Return the new array.
+  const newArr = [];
+  for (let i = 0; i < elements.length; i++) {
+    newArr.push(cb(elements[i]));
+  } return newArr;
 };
 
 const reduce = (elements, cb, startingValue) => {
   // Combine all elements into a single value going from left to right.
   // Elements will be passed one by one into `cb` along with the `startingValue`.
   // `startingValue` should be the first argument passed to `cb` and the array element should be the second argument.
   // `startingValue` is the starting value.  If `startingValue` is undefined then make `elements[0]` the initial value.
+  const comboV = elements.slice();
+  let memo;
+  if (startingValue === undefined) {
+    memo = comboV.shift();
+  } else {
+    memo = startingValue;
+  }
+  each(comboV, (item) => {
+    memo = cb(memo, item);
+  });
+  return memo;
 };
 
 const find = (elements, cb) => {
   // Look through each value in `elements` and pass each element to `cb`.
   // If `cb` returns `true` then return that element.
   // Return `undefined` if no elements pass the truth test.
+  for (let i = 0; i < elements.length; i++) {
+    if (cb(elements[i]) === true) {
+      return elements[i];
+    }
+  }
 };
 
 const filter = (elements, cb) => {
   // Similar to `find` but you will return an array of all elements that passed the truth test
   // Return an empty array if no elements pass the truth test
+  const newArr = [];
+  for (let i = 0; i <= elements.length; i++) {
+    if (cb(elements[i]) === true) {
+      newArr.push(elements[i]);
+    }
+  } return newArr;
 };
 
 /* STRETCH PROBLEM */
diff --git a/src/callbacks.js b/src/callbacks.js
@@ -2,35 +2,54 @@
 
 const firstItem = (arr, cb) => {
   // firstItem passes the first item of the given array to the callback function.
+  cb(arr[0]);
 };
 
 const getLength = (arr, cb) => {
   // getLength passes the length of the array into the callback.
+  cb(arr.length);
 };
 
 const last = (arr, cb) => {
   // last passes the last item of the array into the callback.
+  cb(arr[arr.length-1]);
 };
 
 const sumNums = (x, y, cb) => {
   // sumNums adds two numbers (x, y) and passes the result to the callback.
+  cb( x+y);
 };
 
 const multiplyNums = (x, y, cb) => {
   // multiplyNums multiplies two numbers and passes the result to the callback.
+  cb(x*y);
 };
 
 const contains = (item, list, cb) => {
   // contains checks if an item is present inside of the given array/list.
   // Pass true to the callback if it is, otherwise pass false.
-};
+  for( let i=0;i<list.length;i++){
+    if(list[i]===item){
+      cb(true)}
+      if(list[i]!==item){
+        cb(false)
+    }
+  }
+  };
 
 /* STRETCH PROBLEM */
 
 const removeDuplicates = (array, cb) => {
   // removeDuplicates removes all duplicate values from the given array.
   // Pass the duplicate free array to the callback function.
   // Do not mutate the original array.
+  let newArr=[array[0]];
+  for(let i=1;i<length;i++){
+    if(array[i]!==array[i-1] && (!newArr.includes(array[i]))) {
+     newArr.push(array[i]);
+    }
+  }
+    return cb(newArr); 
 };
 
 /* eslint-enable */
diff --git a/src/objects.js b/src/objects.js
@@ -1,26 +1,35 @@
+
 // Complete the following underscore functions.
 // Reference http://underscorejs.org/ for examples.
 
 const keys = (obj) => {
   // Retrieve all the names of the object's properties.
   // Return the keys as strings in an array.
   // Based on http://underscorejs.org/#keys
+  return Object.keys(obj);
 };
 
 const values = (obj) => {
   // Return all of the values of the object's own properties.
   // Ignore functions
   // http://underscorejs.org/#values
+  return Object.values(obj);
 };
 
 const mapObject = (obj, cb) => {
   // Like map for arrays, but for objects. Transform the value of each property in turn.
   // http://underscorejs.org/#mapObject
+  const myKeys = Object.keys(obj);
+  for (let i = 0; i < myKeys.length; i++) {
+    obj[myKeys[i]] = cb(obj[myKeys]);
+  }
+  return obj;
 };
 
 const pairs = (obj) => {
   // Convert an object into a list of [key, value] pairs.
   // http://underscorejs.org/#pairs
+  return Object.entries(obj);
 };
 
 /* STRETCH PROBLEMS */
