OPENJUDGE 4017 爬楼梯

这就是个Fibonacci数列问题我会乱说？

# include <iostream>

using namespace std;

int Recursion(int level)
{
if ( level == 0 )
{
return 1;
}
else if ( level < 0 )
{
return 0;
}
else return ( Recursion(level-1) + Recursion(level-2) );
}

int main()
{
int stairLevel = 0;
int count = 0;
while ( cin >> stairLevel )
{
count = Recursion(stairLevel);
cout << count << endl;
}
return 0;
}