# This is a sample Python script.
import random
# Press Shift+F10 to execute it or replace it with your code.
# Press Double Shift to search everywhere for classes, files, tool windows, actions, and settings.


def input_wrapper():
#    return inputfile.readline().strip()
     return input()


def print_hi(name):
    line = input_wrapper().split(" ")
    L = int(line[0])
    R = int(line[1])
    C = int(line[2]) % 1000

    start = (L * C) % 1000
    maxer = start
    # startからどれだけ引けば最適になるのか
    for i in range(L, min(R, L+1001)):
        start = (start + C) % 1000
        if start == 0:
            print(0)
            return
        maxer = max(start, maxer)

    print(1000 - maxer)



# Press the green button in the gutter to run the script.
if __name__ == '__main__':
    print_hi('PyCharm')
#    make_charlie()
# See PyCharm help at https://www.jetbrains.com/help/pycharm/