怎么把数学式子用C语言来表达

int main()
{
      float x,y,z,a,b;
      float n,m,k;
      scanf("%f%f%f%f%f,&x,&y,&z,&a,&b);
      n = x/(y+z);
      m = (3.5+b)/(4*(a+b));
      k = (n+m)/3;
      printf("result = %f",k);
      return 0;
}