sdnu1039
#include<cstdio> #include<iostream> #include<algorithm> #include<cmath> #include<cstring> using namespace std; int main() { int n; int i; cin >> n; int f1 = 1,f2 = 1; int fn; if(n<=2) cout << 1 << "\n"; else { for(i=3;i<=n;i++) { fn = f1 + f2; f1 = f2; f2 = fn; } printf("%d\n",fn); } return 0; }sdnu1083
#include<cstdio> #include<iostream> #include<algorithm> using namespace std; int main() { int i,n; int fn; while(cin>>n) { int f1 = 1,f2 = 2,f3 = 4; if(n==1){ cout << "1" << "\n";continue;} else if(n==2) { cout << "2" << "\n";continue;} else if(n==3) { cout << "4" << "\n";continue;} else for(i = 4;i <= n;i++) { fn = f3 + f2 + f1; f1 = f2; f2 = f3; f3 = fn; } cout << fn << "\n"; } return 0; }