Dynamic Programming For Coding Interviews: A Bottom-Up Approach To Problem Solving

I wanted to compute 80th term of the Fibonacci series. I wrote the rampant recursive function int fib(int n){ return (1==n 2==n) ? 1: fib(n-1) + fib(n-2); } and waited for the result. I wait... and wait... and wait... With an 8GB RAM and an Intel i5 CPU why is it taking so long? I terminated the process and tried computing the 40th term. It took about a second. I put a check and was shocked to find that the above recursive function was called 204668309 times while computing the 40th term. ...See More