one question about how to use zhe CUDA in Jetson KT1

Now I get the CUDA and Opencv in the Official website ,I also installing them in my TK1,but I do not kown how to use the CUDA.I want to use of the GPU to speed my programming . I would be grateful ,if anybady can help me .

You might find this of interest:
https://devblogs.nvidia.com/parallelforall/easy-introduction-cuda-c-and-c/
https://devblogs.nvidia.com/parallelforall/even-easier-introduction-cuda/

There are other tutorials, e.g., for use in Python instead of C/C++.