def fx(x):

    return (a*x // b) - a * (x//b)



a,b,n = [int(x) for x in input().split()]



if(n < b):

    print((fx(n)))

else:

    print((fx((n//b)*b -1)))

def fx(x):

    return (a*x // b) - a * (x//b)



a,b,n = [int(x) for x in input().split()]



if(n < b):

    print((fx(n)))

else:

    print((fx(b -1)))
def fx(x):
    return (a * x // b) - a * (x // b)


a, b, n = [int(x) for x in input().split()]
if n < b:
    print((fx(n)))
else:
    print((fx((n // b) * b - 1)))

def fx(x):
    return (a * x // b) - a * (x // b)


a, b, n = [int(x) for x in input().split()]
if n < b:
    print((fx(n)))
else:
    print((fx(b - 1)))

-    print((fx((n // b) * b - 1))) +    print((fx(b - 1)))