chrisleboeuf/exit-study-guide-immerison-precourse

Study Guide for the Precourse Exit Test

Precourse Exit Practice

Requirements Pseudocode everything! Define your "IOCE"

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Input: whatever data type your function accepts i.e (array of objects, string, object, array);

Output: data type that should be returned

Constraints: rules that your implementation must follow

Edge cases: special cases that could produce unintended results

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Make all of your changes in exitPrep.js. Make sure to understand your constraints. A correct answer not following the constraints is wrong. It is better to have attempted the correct problem. Feel free to use the console and the debugger.

Manipulating Collections

• Make 2 functions that randomize the order of an Array's contents. Implement one function that is pure (pureShuffle), and one that modifies the original array (dirtyShuffle).

• Make a function mergeObjects that accepts an unspecified number of objects and updates the first object with the contents of all subsequent objects.

• Make a function semiMergeObjects that performs the same operation as the previous function, but does not replace values at keys that are already present.

Recursion

Create a function replaceValuesInObj that finds all values of a provided name in an Object (and nested Objects) and renames them to a provided new name.

Example:

const obj = {
  golf: {
    zebra: 'charlie',
  },
};

replaceValuesInObj(obj, 'charlie', 'delta');

// returns { golf: { zebra: 'delta' } };

Create a function addKeysToExistingObj that adds a new key/value pair to an Object (and nested Objects).

Example:

const obj = {
  golf: {
    zebra: 'charlie'
  },
};

addKeysToExistingObj(obj, 'foxtrot', 'victor');
// {
//   golf: {
//     zebra: 'charlie',
//     foxtrot: 'victor'
//   },
//   foxtrot: 'victor'
// }

Executing Higher Order Functions

You are provided an Array of Objects representing SNL cast members.

Create a function comediansFilteredAndMapped that returns all the comedians that are:

• cast members added from the year 2005 to present
• cast members whose full name have more than 10 letters

It should:

• Use filter and map
• Make new keys (appearanceNumber, name, and seasonsActive)
• Note: The values cannot be directly mapped to new keys

Do not create any unnecessary storage variables outside your Higher Order Functions. Your result should look like this:

[
  {
    appearanceNumber: '#8',
    name: 'Sterling K. Brown',
    seasonsActive: 6
  },
  {
    appearanceNumber: '#9',
    name: 'Jay Pharoah',
    seasonsActive: 7
  },
  {
    appearanceNumber: '#10',
    name: 'Leslie Jones',
    seasonsActive: 5
  }
]

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Create a function comedianNamesFilteredAndMapped that gets the names of all the comedians that are:

• cast members added from the year 2005 to present
• cast members whose full name have more than 10 letters

It should:

• Use filter and map

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Create a function comediansReduced1 that represents all the comedians that are:

• cast members added from the year 2005 to present
• cast members whose full name have more than 10 letters

It should:

• Use reduce
• Make new keys (appearanceNumber, name, and seasonsActive)

Do not create any unnecessary storage variables outside your Higher Order Functions. Your result should look like this:

[
  {
    appearanceNumber: '#8',
    name: 'Sterling K. Brown',
    seasonsActive: 6
  },
  {
    appearanceNumber: '#9',
    name: 'Jay Pharoah',
    seasonsActive: 7
  },
  {
    appearanceNumber: '#10',
    name: 'Leslie Jones',
    seasonsActive: 5
  }
]

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Create a function comediansReduced2 that represents all the comedian names that are:

• cast members added from the year 2005 to present
• cast members whose full name have more than 10 letters

It should:

• Must use reduce