Problem description
Eleven wants to choose a new name for herself. As a bunch of geeks, her friends suggested an algorithm to choose a name for her. Eleven wants her name to have exactly n characters.
Her friend suggested that her name should only consist of uppercase and lowercase letters 'O'. More precisely, they suggested that the i-th letter of her name should be 'O' (uppercase) if i is a member of Fibonacci sequence, and 'o' (lowercase) otherwise. The letters in the name are numbered from 1 to n. Fibonacci sequence is the sequence f where
- f1 = 1,
- f2 = 1,
- fn = fn - 2 + fn - 1 (n > 2).
As her friends are too young to know what Fibonacci sequence is, they asked you to help Eleven determine her new name.
Input
The first and only line of input contains an integer n (1 ≤ n ≤ 1000).
Output
Print Eleven's new name on the first and only line of output.
Examples
Input
8
Output
OOOoOooO
Input
15
Output
OOOoOooOooooOoo
解题思路：题目已经说的很清楚了，如果第i位是斐波那契数，就输出大写字母'O'，否则输出小写字母'o'，简单水过！
AC代码：
1 #include <bits/stdc++.h> 2 using namespace std; 3 int main() 4 { 5 int n,k=1,f[17]={1,1}; 6 for(int i=2;i<17;++i)//a[16]刚好超过1000，所以只需枚举到16即可 7 f[i]=f[i-2]+f[i-1]; 8 cin>>n; 9 for(int i=1;i<=n;++i){ 10 if(i==f[k]){cout<<'O';k++;} 11 else cout<<'o'; 12 } 13 cout<<endl; 14 return 0; 15 }