def main():
    N, M = map(int, input().split())
    C = list(map(int, input().split()))
    for x in range(M):
        mi = C.index(min(C))
        if C[mi] == 0:
            C.pop(mi)
            mi = C.index(min(C))
        C[mi] -= 1
    if C.count(0) >= 1:
        C.pop(C.index(0))
    
    print(N-len(C))
    
        
    
    
if __name__ == '__main__':
    main()