# No.156 キャンディー・ボックス
n, m = [int(i) for i in input().split()]
c = [int(i) for i in input().split()]

'''
for i in range(m):
    tmp = [c[j] for j in range(n) if c[j] != 0]
    c[c.index(min(tmp))] -= 1

print(n - len([c[i] for i in range(n) if c[i] != 0]))
'''

for i in range(m):
    tmp = [c[j] for j in range(n) if c[j] != 0]
    tmp.sort()
    tmp[0] -= 1

print(n - len([c[i] for i in range(n) if c[i] != 0]))