juanji.cc

#include <iostream>
using namespace std;

template <class T, size_t SizeA, size_t SizeB>
T he(T (&a)[SizeA], T (&b)[SizeB], T ab[])
{
  if(SizeA!=SizeB)
    return 0;
  for(int i=0;i<SizeA;i++) 
    {
      ab[i]=a[i]+b[i];
    }
  return 1;
}

template <class T, size_t SizeA, size_t SizeB>
T nenji(T (&a)[SizeA], T (&b)[SizeB])
{
  if(SizeA!=SizeB)
    return -1;
  double ab=0;
  for(int i=0;i<SizeA;i++) 
    {
      ab+=a[i]*b[i];
    }
  return ab;
}

template <class T, size_t SizeA, size_t SizeB>
T ck(T (&a)[SizeA], T (&b)[SizeB], int k)
{
  T ab=0;
  for(int i=0;i<SizeA;i++)
    {
      for(int j=0;j<SizeB;j++)
	{
	  if(i+j==k)
	    ab+=a[i]*b[j];
	}
    }
  return ab;
}

template <class T, size_t SizeA, size_t SizeB>
int juanji(T (&a)[SizeA], T (&b)[SizeB], T ab[])
{
  int n=SizeA+SizeB-1;
  for(int i=0;i<n;i++)
    {
      ab[i]=ck(a,b,i);
    }
  return 1;
}

template <class T, size_t Size>
void dump(T (&a)[Size])
{
  cout << "{";
  for(int i=0;i<Size;i++)
    {
      cout << a[i];
      if(i<Size-1)
	cout <<  ", ";
    }
  cout << "}" << endl;
}

int main()
{
  double a[]={1,2,4,3};
  double b[]={4,2,8,0};

  dump(a);
  dump(b);

  cout << "he = ";
  double c[sizeof(a)/sizeof(a[0])];
  he(a,b,c);
  dump(c);

  cout << "nenji = " << nenji(a,b) << endl;

  cout << "juanji = ";
  double ab[sizeof(a)/sizeof(a[0])+sizeof(b)/sizeof(b[0])-1];
  juanji(a,b,ab);
  dump(ab);
  cout << endl;

  return 0;
}