Problem9547--ABC239 —— C - Knight Fork

9547: ABC239 —— C - Knight Fork

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

On an $xy$-coordinate plane, is there a lattice point whose distances from two lattice points $(x_1, y_1)$ and $(x_2, y_2)$ are both $\sqrt{5}$?

Notes
A point on an $xy$-coordinate plane whose $x$ and $y$ coordinates are both integers is called a lattice point.  
The distance between two points $(a, b)$ and $(c, d)$ is defined to be the Euclidean distance between them, $\sqrt{(a - c)^2 + (b-d)^2}$.

The following figure illustrates an $xy$-plane with a black circle at $(0, 0)$ and white circles at the lattice points whose distances from $(0, 0)$ are $\sqrt{5}$. (The grid shows where either $x$ or $y$ is an integer.)

Input

Input is given from Standard Input in the following format:

```
$x_1$ $y_1$ $x_2$ $y_2$
```

Output

If there is a lattice point satisfying the condition, print `Yes`; otherwise, print `No`.

Constraints

-   $-10^9 \leq x_1 \leq 10^9$
-   $-10^9 \leq y_1 \leq 10^9$
-   $-10^9 \leq x_2 \leq 10^9$
-   $-10^9 \leq y_2 \leq 10^9$
-   $(x_1, y_1) \neq (x_2, y_2)$
-   All values in input are integers.

Sample 1 Input

0 0 3 3

Sample 1 Output

Yes
  • The distance between points (2,1) and (x1,y1) is $\sqrt{(0−2)^2+(0−1)^2}=5$;
  • the distance between points (2,1) and (x2,y2) is $\sqrt{(3−2)^2+(3−1)^2}=5$;
  • point (2,1) is a lattice point,

so point (2,1) satisfies the condition. Thus, Yes should be printed.
One can also assert in the same way that (1,2) also satisfies the condition.

Sample 2 Input

0 1 2 3

Sample 2 Output

No
No lattice point satisfies the condition, so No should be printed.

Sample 3 Input

1000000000 1000000000 999999999 999999999

Sample 3 Output

Yes
Point $(10^9+1,10^9−2)$ and point $(10^9−2,10^9+1)$ satisfy the condition.

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