N=int(input())
T=list(map(int,input().split()))
T.sort()
sm=0
cmsm=[0]
for i in range(N-1):
    cmsm.append(cmsm[-1]+T[i+1]-T[i])
sm=sum(cmsm)
ans=0
for i in range(N-1):
    if i>0:
        sm-=(T[i]-T[i-1])*(N-i)
    ans+=sm
print(ans)