# Problem 1 - JSON Diff Utility

### Write a utility to compare two JSON documents and generate the differences.

**Example -**

For two json documents -  `clark1.json` and `clark2.json`.

`clark1.json`

```
{
    "name": "Clark Kent",
    "age":"33",
    "work":"Daily Planet",
    "friends": ["Lana Lang"]
}
```

and

`clark2.json`

```
{
    "name": "Clark Kent",
    "age":"34",
    "work":"Daily Planet",
    "associations": ["Justice League"]
}
```

**Diffs (result)**

1. Property `age` is changed from 33 to 34
2. New property `associations` is added with value - `["Justice League"]`
3. Property `friends` is deleted

>**Note:** You can define your own format/type to represent a diff.

### In addition, you should be able to create a new JSON document from a base JSON document and a list of differences.

**Example -**

For a json document -  `clark1.json`

```
{
    "name": "Clark Kent",
    "age":"33",
    "work":"Daily Planet",
    "friends": ["Lana Lang"]
}
```

And a list of diff -
1. Property `age` is changed from 33 to 34
2. New property `associations` is added with value - `["Justice League"]`
3. Property `friends` is deleted

You should be able to create a new JSON -

```
{
    "name": "Clark Kent",
    "age":"34",
    "work":"Daily Planet",
    "associations": ["Justice League"]
}
```

**APIs**

`List<Diff> diff(String jsonA, String jsonB)`

`String patch(String jsonA, List<Diff>)`

---

# Problem 2 - Expression evaluator

You will be provided with two strings - `expression` and `values`. `expression` represents a mathematical expression with some variables. `values` will provide the values of the variables in the expression in the following format -

`key=value;...;key=value`

**Example 1-**

`expression` - `"x^2 + 2x + 1"`

`values` - `"x=5"`

*Result* = 36

**Example 2 (with a trigonometric function)-**

`expression` - `"x^2 + 2x + 1 + sin(y)"`

`values` - `"x=5;y=π/2"`

**Result** = 37

**Example 3 (with a decimal number)-**

`expression` - `"x^2 + 2.5y + 1 + sin(z)"`

`values` - `"x=5;y=4;z=π/2"`

**Result** = 37


### Symbols and meanings

1. `sin` - sine trigonometric function
2. `cos` - cosine trigonometric function
3. `tan` - tangent trigonometric function
4. `log` - logarithm function
5. `x^y` - `x` raised to power `y`
6. `xy` - product of `x` and `y`
7. `x/y` - `x` divided by `y`
8. `x+y` - sum of `x` and `y`
9. `x-y` - difference of `x` and `y`
10. `()` - parenthesis
11. `π` - Mathematical constant PI

**APIs**

`double evaluate(String expression, String values)`

---
### Completion Date - `October 31, 2019`
### Programming Language - `Java`