num = input().split()

m = int(num[0])

t = int(num[1])

s = int(num[2])

if t == 0:

print(0)

else:

if s % t == 0 or s<t:
    number = s // t
    remaining_apples = m - number if number <= m else 0
    print(remaining_apples)
elif s%t!=0 and s>t:
    number = s // t
    remaining_apples = m - number if number <= m else 0
    print(remaining_apples - 1)