import sys

input = sys.stdin.readline

import math

import collections

def I(): return int(eval(input()))

def MI(): return list(map(int, input().split()))

def LI(): return list(map(int, input().split()))



r=I()

print((3*r*r))
def main():

    import sys

    input = sys.stdin.readline

    sys.setrecursionlimit(10**7)

    from collections import Counter, deque

    from collections import defaultdict

    from itertools import combinations, permutations, accumulate, groupby, product

    from bisect import bisect_left,bisect_right

    from heapq import heapify, heappop, heappush

    from math import floor, ceil,pi,factorial

    from operator import itemgetter

    def I(): return int(eval(input()))

    def MI(): return list(map(int, input().split()))

    def LI(): return list(map(int, input().split()))

    def LI2(): return [int(eval(input())) for i in range(n)]

    def MXI(): return [[LI()]for i in range(n)]

    def SI(): return input().rstrip()

    def printns(x): print(('\n'.join(x)))

    def printni(x): print(('\n'.join(list(map(str,x)))))

    inf = 10**17

    mod = 10**9 + 7

#main code here!

    r=I()

    print((3*r**2))

            

            

            

    



        

    

            

        



        

if __name__=="__main__":

    main()

import sys

input = sys.stdin.readline
import math
import collections


def I():
    return int(eval(input()))


def MI():
    return list(map(int, input().split()))


def LI():
    return list(map(int, input().split()))


r = I()
print((3 * r * r))

def main():
    import sys

    input = sys.stdin.readline
    sys.setrecursionlimit(10**7)
    from collections import Counter, deque
    from collections import defaultdict
    from itertools import combinations, permutations, accumulate, groupby, product
    from bisect import bisect_left, bisect_right
    from heapq import heapify, heappop, heappush
    from math import floor, ceil, pi, factorial
    from operator import itemgetter

    def I():
        return int(eval(input()))

    def MI():
        return list(map(int, input().split()))

    def LI():
        return list(map(int, input().split()))

    def LI2():
        return [int(eval(input())) for i in range(n)]

    def MXI():
        return [[LI()] for i in range(n)]

    def SI():
        return input().rstrip()

    def printns(x):
        print(("\n".join(x)))

    def printni(x):
        print(("\n".join(list(map(str, x)))))

    inf = 10**17
    mod = 10**9 + 7
    # main code here!
    r = I()
    print((3 * r**2))


if __name__ == "__main__":
    main()

-import sys +def main(): +    import sys -input = sys.stdin.readline -import math -import collections +    input = sys.stdin.readline +    sys.setrecursionlimit(10**7) +    from collections import Counter, deque +    from collections import defaultdict +    from itertools import combinations, permutations, accumulate, groupby, product +    from bisect import bisect_left, bisect_right +    from heapq import heapify, heappop, heappush +    from math import floor, ceil, pi, factorial +    from operator import itemgetter + +    def I(): +        return int(eval(input())) + +    def MI(): +        return list(map(int, input().split())) + +    def LI(): +        return list(map(int, input().split())) + +    def LI2(): +        return [int(eval(input())) for i in range(n)] + +    def MXI(): +        return [[LI()] for i in range(n)] + +    def SI(): +        return input().rstrip() + +    def printns(x): +        print(("\n".join(x))) + +    def printni(x): +        print(("\n".join(list(map(str, x))))) + +    inf = 10**17 +    mod = 10**9 + 7 +    # main code here! +    r = I() +    print((3 * r**2)) -def I(): -    return int(eval(input())) - - -def MI(): -    return list(map(int, input().split())) - - -def LI(): -    return list(map(int, input().split())) - - -r = I() -print((3 * r * r)) +if __name__ == "__main__": +    main()