B = int(input())
N = int(input())
C=[]
for i in range(N):
    C.append(int(input()))

C.sort()
C.reverse()
C_sum=sum(C)
ave=int(C_sum/N)

sum_min=0xFFFFFFFF
# min_index=0
for i in range(ave-1,ave+2):
    tmp_sum=0
    for j in range(N):
        tmp_sum+=abs(C[j]-i)
    if tmp_sum<sum_min:
        sum_min=tmp_sum
        # min_index=i
    # print(i,ave,tmp_sum,sum_min)
print(int(sum_min))