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Duty

Ministry of health decided to sanitize streets of city D. In order to do it a crew of highly skilled doctors has been formed. City has \textbf{N} hospitals, which are connected by \textbf{M} paths. For sanitization of paths between hospitals, the crew needs to go through every path exactly once and return to the original point. Since it’s not always possible, crew can be teleported. Teleportation is quite expensive for the ministry operation, so it should be used as seldom as possible. There can be many paths between same hospitals, same as there could be paths that connect hospital to itself. Crew can start its path at any hospital. Difficult task to minimize expenses has been assigned to Watson by Ministry. He has activated all its neural chips and dove into calculations. Rybka volunteered to help and find simpler way to solve the task. \InputFile The first line contains two integers \textbf{N} and \textbf{M} (\textbf{1} ≤ \textbf{N}, \textbf{M} < \textbf{10^5}). Following \textbf{M} lines each contains two integers \textbf{i j}, describing path between hospitals \textbf{i} and \textbf{j} (\textbf{1} ≤ \textbf{i}, \textbf{j} ≤ \textbf{N}). \OutputFile You need to print minimal possible number of teleportations.
Time limit 0.5 seconds
Memory limit 16 MiB
Input example #1
4 6
1 2
2 3
3 4
4 1
1 3
2 4
Output example #1
2