P4995 跳跳！ - 洛谷 | 计算机科学教育新生态 (luogu.com.cn)

n = int(input())
data = list(map(int,input().split()))
data.append(0)
data.sort()sum = 0
l = 0
r = len(data)-1
flag = 1
while l<=r:sum += (data[l]-data[r])**2if flag:l += 1flag = 0else:r -= 1flag = 1
print(sum)