Circle Area with a PI Constant

Declare final double PI = 3.14159; and use it to compute the area of a circle from its radius.

Input: one integer — the radius.

Output: one line — the area (PI x radius x radius) rounded to two decimal places.

Example 1

Input

Output

78.54

1 <= radius <= 100000
Use PI = 3.14159 exactly.

Hint 1

double area = PI * r * r;

Hint 2

String.format(Locale.US, "%.2f", area) rounds to two places.

Give the fixed value 3.14159 a name with final so it cannot be changed by mistake and the formula reads clearly. Format the double result to two decimals with Locale.US so the output is stable.

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Input (stdin)

Output