text: //Thred Block Example
  #include <stdio.h>
  
  #define NUM_BLOCKS 16
  #define BLOCK_WIDTH 1
  
  __global__ void hello(){
  	printf("Hello world! I'm a thread in block %d\n", blockIdx.x);
  }
  
  int main(int argc, char **argv){
  	//launch the kernel 
  	hello<<<NUM_BLOCKS, BLOCK_WIDTH>>>();
  
  	//force the printf()s to flush
  	cudaDeviceSynchronize();
  
  	printf("That's all!\n");
  
  	return 0;
  }