2_par_sum.cu

#include <stdio.h>

#define N 10

__global__ void sum(int *a,
         int *b, int *c)
{
  int i = blockIdx.x;
  c[i] = a[i] + b[i];
}


int main( void ) {

	int host_a[N];
	int host_b[N];
	int host_c[N];
	
	for (int i=0; i<N; i++) {
		host_a[i] = i;
		host_b[i] = i;
	}

int *dev_a, *dev_b, *dev_c;
	cudaMalloc(&dev_a, sizeof(int) * N);
	cudaMalloc(&dev_b, sizeof(int) * N);
	cudaMalloc(&dev_c, sizeof(int) * N);
	cudaMemcpy(dev_a, host_a, sizeof(int) * N, cudaMemcpyHostToDevice);
	cudaMemcpy(dev_b, host_b, sizeof(int) * N,
         cudaMemcpyHostToDevice);
		 
		 sum<<<N, 1>>>(dev_a, dev_b, dev_c);

	cudaMemcpy(host_c, dev_c, sizeof(int) * N, cudaMemcpyDeviceToHost);
	
	for (int i=0; i<N; i++) {
		printf("%d ", host_c[i]);
	}
	printf("\n");

}