#include <stdio.h>

void flushstdin(); /* borra el buffer stdin */

int main(int argc, char * argv[])
{
  double v, sum;
  char buff[100];
  sum = 0.0;
  v = 0.0;
  char op = '\0';
  int salir2;

   while( op != 'q'  )
   {
	  fgets(buff, sizeof(buff), stdin);
      salir2 = sscanf(buff,"%lf",&v); 
      if( !salir2 )
	  {
		op = buff[0];
        printf("op %c\n",op);
		continue;
      }
      switch(op)
      {
      case '+':
        fprintf(stdout,"v: %f \t%.2f\n",v,sum += v); 
        break;
      case '-':
        printf("v: %f \t%.2f\n",v,sum -= v); 
        break;
      case '*':
        printf("v: %f \t%.2f\n",v,sum *= v); 
        break;
      case '/':
        printf("v: %f \t%.2f\n",v,sum /= v); 
        break;
	  case 'q':
        break;
      default:  /* opcion no valida */
		printf(" Operador no valido \n");
      }
    }
  fprintf(stdout,"salimos\n");
  fprintf(stderr,"salio todo bien\n");
  return 0;
}

void flushstdin()
{
    int c;
    while ((c = getchar()) != '\n' && c != EOF);
}