There is a gift which costs you Z tokens. There is a general machine which provides you 2 tokens/second .\nIf you get X tokens then with that tokens you can buy a special machine which provides you an extra Y tokens (you can also use general machine same time) . Print minimum time taken to buy the gift.\n\n**Note** **:** Neglect time of buying special machine and more than one special machines can be bought\n\n**Input format :** X Y Z (given)\n\n**Input :** 4 5 10\n**Output :** 4\n\nAny ideas???

There is a gift which costs you Z tokens. There is a general machine which provides you 2 tokens/second .\nIf you get X tokens then with that tokens you can buy