atcoder#ABC191D. [ABC191D] Circle Lattice Points

[ABC191D] Circle Lattice Points

Score : 400400 points

Problem Statement

We have a circle of radius RR centered at (X,Y)(X, Y). Find the number of grid points (points whose xx- and yy-coordinates are both integers) within or on the circle.

Constraints

  • X105|X| \le 10^5
  • Y105|Y| \le 10^5
  • 0<R1050 \lt R \le 10^5
  • Each of XX, YY, and RR has at most four digits after the decimal point.

Input

Input is given from Standard Input in the following format:

XX YY RR

Output

Print the answer.

0.2 0.8 1.1
3

The circle is shown below. The grid points within or on the circle are marked red.

Figure

100 100 1
5

XX, YY, and RR may not have decimal points. Note that we also count the grid points on the circle.

42782.4720 31949.0192 99999.99
31415920098