i tried the big int but i dont know wht the prob is . i used the class big int to simulate this. pliz help;here is my code
#include <iostream.h>
#include <stdio.h>
#include <ctype.h>
#include <math.h>
#include <string.h>
int BigIntMajorVersion = 6;
int BigIntMinorVersion = 7;
int BigIntRevision = 25;
typedef unsigned int SizeT;
typedef unsigned int DATATYPE;
const DATATYPE BASE = 10000;
const DATATYPE INVALIDDATA = 65535U;
const SizeT LOG10BASE = 4;
class BigInteger
{
private:
DATATYPE *TheNumber;
SizeT Start;
SizeT End;
bool isNegative;
BigInteger(SizeT,DATATYPE,bool);
void datacopy(BigInteger const&,SizeT);
SizeT datalen(DATATYPE const*) const;
void deallocateBigInteger();
void TrimZeros();
void Set(DATATYPE);
public:
BigInteger();
BigInteger(long);
BigInteger(char const*);
BigInteger(BigInteger const&);
~BigInteger();
int UnsignedCompareTo(BigInteger const&)const;
int CompareTo(BigInteger const&)const;
SizeT Digits() const;
bool isValidNumber() const;
bool isZero()const;
BigInteger& Add(BigInteger const&) const;
BigInteger& Subtract(BigInteger const&) const;
BigInteger& Multiply(BigInteger const&) const;
BigInteger& Multiply(DATATYPE const&) const;
BigInteger& DivideAndRemainder(BigInteger const&,BigInteger&,bool) const;
BigInteger& DivideAndRemainder(DATATYPE const&,DATATYPE&,bool) const;
friend BigInteger& operator+(BigInteger const&, BigInteger const&);
friend BigInteger& operator-(BigInteger const&, BigInteger const&);
friend BigInteger& operator*(BigInteger const&, BigInteger const&);
friend BigInteger& operator*(BigInteger const&, DATATYPE const&);
friend BigInteger& operator*(DATATYPE const&, BigInteger const&);
friend BigInteger& DivideAndRemainder(BigInteger const&, BigInteger const&,BigInteger&,bool);
friend BigInteger& DivideAndRemainder(BigInteger const&, DATATYPE const&,DATATYPE&,bool);
friend BigInteger& operator/(BigInteger const&, BigInteger const&);
friend BigInteger& operator/(BigInteger const&, DATATYPE const&);
friend BigInteger& operator/(DATATYPE const&, BigInteger const&);
friend BigInteger& operator%(BigInteger const&, BigInteger const&);
friend BigInteger& operator%(BigInteger const&, DATATYPE const&);
friend BigInteger& operator%(DATATYPE const&, BigInteger const&);
BigInteger& operator=(BigInteger const&);
friend ostream& operator<<(ostream& , BigInteger const&);
friend istream& operator>>(istream& , BigInteger& );
BigInteger& operator++();
BigInteger& operator++(int);
BigInteger& operator--();
BigInteger& operator--(int);
BigInteger& operator-();
BigInteger& operator<<(SizeT);
BigInteger& operator>>(SizeT);
void abs();
friend BigInteger& abs(BigInteger&);
int toInt();
long toLong();
BigInteger& Power(long )const;
BigInteger& SquareRoot() const;
};
here is the main
BigInteger zero("0"), one("1");
BigInteger two(2);
BigInteger fib[5010];
int main(){
register int i, num;
fib[0] = zero;
fib[1] = one;
freopen("input.in","rt",stdin);
for(i = 2; i <= 5005; i++)
{
fib
= fib[i-1] + fib[i-2];
}
while(scanf("%d", &num) != EOF)
{
cout<<fib[num]<<endl;
}
return 0;
return 0;
}
sorry for being stupid and to send such a big code . looking forward for u r help.
Riyad 
HOLD ME NOW ,, I AM 6 FEET FROM THE EDGE AND I AM THINKIN.. MAY BE SIX FEET IS SO FAR DOWN