int main(void)
{
int n;
int Fi_num;
while (scanf("%d", &n)==1)
printf("%d\n", Fibonacci(n));
return 0;
}
int Fibonacci(int n)
{
int num;
int n1 = 1, n2 = 1;
int n3;
if (n>2)
for (size_t i = 0; i < n-2; ++i)
{
n3 = n1 + n2;
n1 = n2;
n2 = n3;
}
else
n3 = n1;
return n3;
}