def main():

    A, B, C = list(map(int, input().split()))



    ans = C - (A - B)



    print((max(ans, 0)))





if __name__ == "__main__":

    main()

def main():

    A, B, C = list(map(int, input().split()))



    t = min(A - B, C)

    ans = C - t



    print(ans)





if __name__ == "__main__":

    main()

def main():
    A, B, C = list(map(int, input().split()))
    ans = C - (A - B)
    print((max(ans, 0)))


if __name__ == "__main__":
    main()

def main():
    A, B, C = list(map(int, input().split()))
    t = min(A - B, C)
    ans = C - t
    print(ans)


if __name__ == "__main__":
    main()

-    ans = C - (A - B) -    print((max(ans, 0))) +    t = min(A - B, C) +    ans = C - t +    print(ans)