#include <cuda_runtime.h>
#include <iostream>

int cuda_devices(void) {
    int result = 0;
    cudaGetDeviceCount(&result);
    return result;
}

int main(void) {
    std::cout << "Compiled against CUDA version: " << CUDART_VERSION << "\n";

    int runtime_version = 0;
    switch (cudaError_t r = cudaRuntimeGetVersion(&runtime_version)) {
        case cudaSuccess:
            std::cout << "CUDA runtime version: " << runtime_version << "\n";
            break;
        case cudaErrorNoDevice:
            std::cout << "No CUDA hardware found. Exiting.\n";
            return 0;
        default:
            std::cout << "Couldn't obtain CUDA runtime version (error " << r << "). Exiting.\n";
            return -1;
    }

    int n = cuda_devices();
    std::cout << "Found " << n << " CUDA devices.\n";
    return 0;
}