You went shopping to buy cakes and donuts with X yen (the currency of Japan).

First, you bought one cake for A yen at a cake shop. Then, you bought as many donuts as possible for B yen each, at a donut shop.

How much do you have left after shopping?

Constraints

* 1 \leq A, B \leq 1 000
* A + B \leq X \leq 10 000
* X, A and B are integers.

Input

Input is given from Standard Input in the following format:


X
A
B


Output

Print the amount you have left after shopping.

Examples

Input

1234
150
100


Output

84


Input

1000
108
108


Output

28


Input

579
123
456


Output

0


Input

7477
549
593


Output

405


from fractions import gcd
from math import factorial, ceil, sqrt, atan2, log
from itertools import *
import string
import copy
import random
import bisect
from decimal import *
def id_generator(size=20, chars=string.digits):
    return ''.join(random.choice(chars) for _ in range(size))
 
def mp():
    return map(int,str(raw_input()).split())

x=input()
a=input()
b=input()
print (x-a)%b