#include <iostream>
int a(int n, int a0 = 0, int a1 = 1)
{
if(n <= 0)
return a0;
return a(n-1, a1, a0+a1);
}
int main()
{
using namespace std;
for(int i = 0; i < 10; ++i)
cout << "a(" << i << ") = " << a(i) << endl;
return 0;
}
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