vec_add.cu

#include <iostream>

__global__ void vectorAdd(const float* A, const float* B, float* C, int n){
    int i = blockIdx.x * blockDim.x + threadIdx.x;
    if (i < n){
        C[i] = A[i] + B[i];
    }
}

    int main(){
        const int n = 32;
        size_t size = n * sizeof(float);

        float h_A[n], h_B[n], h_C[n];

        for(int i = 0; i < n; i++){
            h_A[i] = static_cast<float>(i);
            h_B[i] = static_cast<float>(i * 2);
        }

        float *d_A, *d_B, *d_C;
        cudaMalloc((void**)&d_A, size);
        cudaMalloc((void**)&d_B, size);
        cudaMalloc((void**)&d_C, size);

        cudaMemcpy(d_A, h_A, size, cudaMemcpyHostToDevice);
        cudaMemcpy(d_B, h_B, size, cudaMemcpyHostToDevice);

        vectorAdd<<<1, 32>>>(d_A, d_B, d_C, n);

        cudaMemcpy(h_C, d_C, size, cudaMemcpyDeviceToHost);

        for(int i = 0; i < n; i++){
            std::cout << h_C[i] << " ";
        }
        std::cout << std::endl;

        cudaFree(d_A);
        cudaFree(d_B);
        cudaFree(d_C);

        return 0;
}