#Uses python3

import sys

def getMaxDotProduct(a, b):
    a.sort()
    b.sort()
    result = 0
    for i, j in zip(a,b):
        result = result + i*j
    return result

if __name__ == '__main__':
    input = sys.stdin.read()
    data = list(map(int, input.split()))
    n = data[0]
    a = data[1:(n + 1)]
    b = data[(n + 1):]
    print(getMaxDotProduct(a, b))