q3.cpp

//Jorge Samir Godinez Lara/ A01630155
#include <iostream>
using namespace std;
long long Fibonacci(long n){
 long a=0, b=1, c=a+b;
 if(n==0) return 0;
 if(n==1) return 1;
 if(n>=3){
 for(long i=3;i<=n;i++){
 a=b;
 b=c;
 c=a+b; }
 return c;
}
}

int main(){
long num;
cout<<"give me a number: ";
cin>>num;
cout<<"Fibonacci of you number is: " <<Fibonacci(num)<<endl;
return 0;
}