B = int(raw_input())
N = int(raw_input())
C = sorted([int(raw_input()) for i in xrange(N)])

ans = 10**18
for c in C:
    b = sum(c - C[i] for i in xrange(N))
    if b > B: continue
    ans = min(ans, sum(abs(C[i] - c) for i in xrange(N)))
print ans