Week 1 exercises

1_PM/madlibs.js

@@ -10,9 +10,10 @@ const verb1 = ______
 
 Change thses values to generate a different story
 */
-
+const noun1 = 'David'
+const verb1 = 'sing'
 const story = `
-**replace this with your story using a template string**
+${noun1} went to school to ${verb1}.
 `
 
 console.log(story)

1_PM/object.js

@@ -10,6 +10,13 @@ const assert = require('assert')
  */
 
 const hasFalsyValue = obj => {
+  for (var key in obj) 
+  {
+    if ((typeof obj[key] === 'object' && hasFalsyValue(obj[key])) || !obj[key]) 
+      return true;
+
+  }
+  return false;
 };
 
 const falsyObj = {

1_PM/query.js

@@ -101,24 +101,54 @@ dont hard code solutions. */
 
 // Implement the function usersByPet to return a list of user objects filtered by cat or dog.
 const usersByPet = pet => {
+  let users = database['users']
+  let temp = users.filter((x) => {return x['favPet'] === pet;})
+  return temp
 }
 console.log(usersByPet('dog'))
 console.log(usersByPet('cat'))
 
 // Implement the function collegeLookup to return the name and color of a user's college.
 const collegeLookup = user => {
+  let users = database['users']
+  let student = users.filter((x) => {return x['firstName'] === user;})[0]
+  let college = database['college'].filter((x) => {return x['id'] === student['collegeId'] })[0]
+  return [college['name'], college['color']]
 }
 console.log(collegeLookup('Charles'))
 console.log(collegeLookup('Daniela'))
 
 // define oppositesAttract as a list of friend objects whose favorite pets are different.
-const oppositesAttract = _______
+let opp = []
+let users = database['users']
+let friends = database['friends']
+friends.forEach(function (pair)
+{
+  var p1 = users.filter((x) => x['id'] === pair['id1'])[0];
+  var p2 = users.filter((x) => x['id'] === pair['id2'])[0];
+  if(p1['favPet'] !== p2['favPet'])
+    opp.push(pair) 
+});
+const oppositesAttract = opp
 console.log(oppositesAttract)
 
 // define local as a list of users who live in the same state as they go to school.
-const local = _______
+let ans = []
+users.forEach(function (x) {
+  var college = database['college'].filter((c) => {return c['id'] === x['collegeId']})[0]
+  if(x['state'] === college['state'])
+    ans.push(x)
+})
+const local = ans
 console.log(local)
 
 // define collegeFriends as a list of friend objects that go to the same college
-const collegeFriends = _______
+let matches = []
+friends.forEach(function (pair) {
+  var p1 = users.filter((x) => x['id'] === pair['id1'])[0];
+  var p2 = users.filter((x) => x['id'] === pair['id2'])[0];
+  if(p1['collegeId'] === p2['collegeId'])
+    matches.push(pair)
+});
+const collegeFriends = matches;
 console.log(collegeFriends)

1_PM/reduce.js

@@ -5,10 +5,15 @@ const assert = require('assert')
  * returns the sum of its values. e.g. [0,4,3,6,9].reduce(sum, 0) === 22
  */
 
-const sum = (acc, cur) => {};
+const sum = (acc, cur) => {return acc + cur};
 
 Array.prototype.reduce = function(fun, init) {
-
+    let result = init;
+    for(const x of this)
+    {
+        result = fun(result, x);
+    }
+    return result;
 };
 
 const arr1 = [0, 1, 2, 3, 4];

1_PM/scope.js

@@ -1,7 +1,9 @@
 /**
  * Part 1:
  *    What will print and why?
+ *    It will print 1, 2, and undefined
  *    What will change if we delete line 15? Why?
+ *    If we delete line 15, it will print 1, 2, 1 because the value of a is defined  globally in line 25
  * 
  * Part 2:
  *    Change to ES6 syntax (use arrow functions and change var to let).
@@ -12,7 +14,7 @@
  */
 
 function x() {
-  var a;
+  var a = 2;
   console.log(a);
 }
 
@@ -22,6 +24,6 @@ function y() {
   x();
 }
 
-var a = 1;
+let a = 1;
 console.log(a);
 y();