Submission #1530817

---

Source Code Expand

from collections import defaultdict
from itertools import product
from math import pi


def main():
    N = int(input())
    r_list = list(sorted([int(input()) for _ in range(N)], reverse=True))
    ans = 0
    for i, r in enumerate(r_list):
        area = r * r * pi
        if i % 2 == 0:
            ans += area
        else:
            ans -= area
    print("{0:0.7f}".format(ans))


if __name__ == '__main__':
    main()

Submission Info

Judge Result