Internet Service Providers#1374
A group of Internet Service Provider companies (ISPs) use a private communication channel with a maximum capacity of traffic units per second. Each company transfers traffic units per second through the channel and receives a profit directly proportional to the factor T(C-TN). The task is to compute T_{optim}, the smallest positive integer value of that maximizes the total profit the ISPs can obtain from using the channel. Note that , , , and T_{optim} are integers.
Write a program that reads sets of data from an input text file. Each set corresponds to a problem instance and contains two integers and (0 \leq N, C \leq 10^9), separated by spaces. The input ends with end of file.
For each data set, the program outputs the value of T_{optim} according to the problem instance, starting from a new line. The output must have no empty lines.
Example 1