import sys
#input = sys.stdin.readline
#input = sys.stdin.buffer.readline #文字列はダメ
#sys.setrecursionlimit(1000000)
#import math
#import bisect
#import itertools
#import random
#from heapq import heapify, heappop, heappush
from collections import defaultdict
from collections import deque
import copy #DeepCopy: hoge = [_[:] for _ in hogehoge]
#from functools import lru_cache
#@lru_cache(maxsize=None)
MOD = pow(10,9) + 7
#MOD = 998244353
dx = [1,0,-1,0]
dy = [0,1,0,-1]
#dx8 = [1,1,0,-1,-1,-1,0,1]
#dy8 = [0,1,1,1,0,-1,-1,-1]

def main():
    a,b,c = map(int,input().split())
    ans = []
    if c%a == 0:
        ans.append(c//a)
    if (b+c)%a == 0:
            ans.append((b+c)//a)
    if len(ans) == 0:
        print(-1)
    else:
        for ret in ans:
            print(ret)

if __name__ == '__main__':
    main()