You ask any one of the two boys: "What would the other boy tell me if I ask him which is the correct road?"

Vlad

>You go on a long road, and get to a road cross. You can choose from two possibilities: to go rightward or to go leftward. You donnot know which is the correct road. But there are two boys standing there. One of them is always lies, but the other one always tells the thruth. They both know the correct road for you. You donnot know which of them is the lier. You can ask only one question, but only one of them. What would you ask?
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