#include <iostream> using namespace std; int main() { long n,i,a,b,c; cin>>n; if(n==1||n==2)cout<<"1"; else { a=1; b=1; for(i=3;i<=n;++i) { c=a+b; a=b; b=c; } cout<<c; } return 0; }
#include <iostream> using namespace std; int main() { long n,i,a,b,c; cin>>n; if(n==1||n==2)cout<<"1"; else { a=1; b=1; for(i=3;i<=n;++i) { c=a+b; a=b; b=c; } cout<<c; } return 0; }