Self-describing Sequence ACM

这道题改用数组做的话，效率会更高。我用的是向量。解题思路很简单，就是按照顺序将f(n)列出来，输出你要的那个值。

// Self-describing Sequence.cpp : Defines the entry point for the console application.//#include "stdafx.h"#include <vector>#include <iostream>using namespace std;int _tmain(int argc, _TCHAR* argv[]){long n;vector<long> f;while(cin>>n){if(n==0)break;f.push_back(1);f.push_back(2);f.push_back(2);long i=2;long z=3;while(z<=n){//if(z==n)break;long x=1;while(x<=f[i]){//if(z==n)break;f.push_back(i+1);++z;++x;}++i;}cout<<f[n-1]<<"/n";f.clear();}vector<long>().swap(f);system("pause");return 0;}