City Road Maintenance

A city has a number of roads connecting different neighborhoods. In certain cases, two neighborhoods might be linked indirectly through other neighborhoods. You want to find out if there is a route from a starting neighborhood to a target neighborhood. Write a program that takes a list of roads and checks for the existence of a path from the starting neighborhood to the target neighborhood. Input Format: - The first line contains an integer n (number of neighborhoods). - The second line contains an integer m (number of roads). - The next m lines contain two integers a and b representing a road between neighborhoods a and b. - The last line contains two integers start and target, the neighborhoods to check. Output Format: - Print "YES" if a route exists, otherwise print "NO". Example: Input: 4 3 1 2 2 3 1 4 4 3 Output: YES