Здравствуйте, Аршавин Александр Абрамович!
Решение 1й задачи:

Приложение:
#include <fstream>
#include <string>
#include <vector>

using namespace std;

class longnum
{
private:
typedef unsigned __int32 datatype;
typedef unsigned __int64 extdatatype;
typedef vector<datatype>::iterator itertype;
typedef vector<datatype>::reverse_iterator ritertype;
vector<datatype> _data;
static const datatype div=1000000000;
static const datatype num=9;
public:
longnum(datatype val=0)
{
_data.push_back(val);
}
longnum operator=(datatype val)
{
_data.clear();
_data.push_back(val);
return *this;
}
longnum operator*(datatype val)
{
longnum res(*this);
datatype carry=0;
for(itertype it=res._data.begin();it!=res._data.end();it++)
{
extdatatype tmp=static_cast<extdatatype>(*it)*val+carry;
*it=tmp%div;
carry=static_cast<datatype>(tmp/div);
}
if(carry)res._data.push_back(carry);
return res;
}
longnum operator*(longnum& val)
{
longnum res;
res._data.resize(_data.size()+val._data.size(),0);
for(itertype valit=val._data.begin();valit!=val._data.end();valit++)
{
vector<datatype> tmpdata(_data.size()+val._data.size(),0);
itertype tmpit=tmpdata.begin()+(valit-val._data.begin());
datatype carry=0;
extdatatype tmp;
for(itertype it=_data.begin();it!=_data.end();it++,tmpit++)
{
tmp=static_cast<extdatatype>(*it)**valit+carry;
*tmpit=tmp%div;
carry=static_cast<datatype>(tmp/div);
}
*tmpit=carry;
carry=0;
for(itertype tmpit=tmpdata.begin(),resit=res._data.begin();tmpit!=tmpdata.end();tmpit++,resit++)
{
tmp=static_cast<extdatatype>(*tmpit)+*resit+carry;
*resit=tmp%div;
carry=static_cast<datatype>(tmp/div);
}
}
return res;
}
friend ostream& operator<<(ostream& stream,longnum val);
};

ostream& operator<<(ostream& stream,longnum val)
{
bool f=false;
for(longnum::ritertype it=val._data.rbegin();it!=val._data.rend();it++)
{
if(!f)
{
if(*it)
{
f=true;
stream<<*it;
}
}
else
{
char buf[10];
_itoa(*it,buf,10);
string str=buf;
while(str.length()<longnum::num)str="0"+str;
stream<<str;
}
}
if(!f)stream<<"0";
return stream;
};

longnum calc(unsigned int N)
{
if(N)
{
if(N==1)return 45;
else
{
unsigned int t=N/2;
return calc(t)*calc(N-t);
}
}
else return 0;
}

int main()
{
unsigned int N;
ifstream in("INPUT.TXT");
ofstream out("OUTPUT.TXT");
in>>N;
out<<calc(N)<<endl;
return 0;
}