Equality Check

Time limit1sMemory limit512 MB

Summary

Read a quiz line formatted as 'a + b = c' and print YES if a + b equals c, otherwise NO.

Level: Easy1 of 10
Topics: Implementation, Math
Solved: No attempts yet

Problem

You are grading an arithmetic quiz. The quiz asks a student for the sum of two numbers, and the student writes down one answer. Decide whether that answer is correct.

Input

The first and only line contains a string of the form a + b = c. Each of $a$ , $b$ , $c$ is a single-digit positive integer, so $1 \le a, b, c \le 9$ . The line is exactly 9 characters long, with one space between every number and symbol.

Output

Print YES on the first line if the sum is correct, and NO otherwise.

Examples4

Example 1
Input
```
1 + 2 = 3
```
Expected output
```
YES
```
Example 2
Input
```
2 + 2 = 5
```
Expected output
```
NO
```
Example 3
Input
```
1 + 1 = 2
```
Expected output
```
YES
```
Example 4
Input
```
4 + 5 = 9
```
Expected output
```
YES
```