2818 密码

思路：要计算周期，不然会超时。

#include <iostream>
#include <stdio.h>
using namespace std;
int a[202];
int main(){
	int n;
	int k;
	int same;
	cin >> n;
	while(n != 0){
		for(int i = 0; i < n; i++){
			cin >> a[i];
		}
		
		same = 0;
	//	int atmp[n];
		int atmp = 1;
		int round[n];
		for(int i = 0; i < n; i++){
			round[i] = 0;
		}
//		for(int i = 0; i < n; i++){
//			atmp[i] = a[i];
//		}
		for(int i = 0; i < n; i++){
			atmp = a[i];
			while(1){
				atmp = a[atmp-1];
				round[i]++;
				if(atmp == a[i])
					break;
				//cout<<atmp;
			}
		}
//		for(int i = 0; i < n; i++)
//		cout<<round[i]<<" ";
//		cout<<endl;
		
		cin >> k;
		int pos;
		char text[n+1];
		char textTemp[n+1];
	
		while(k != 0){
			for(int i = 0; i < n; i++)	text[i] = ' ';
			text[n] = '\0';
			pos = 0;
			getchar();
			text[0] = getchar();
			while(text[pos] != '\n'){
				pos++;
				text[pos] = getchar();
			}
			text[pos] = ' ';
		//	while(k != 0){
			int ttmp;
			for(int i = 0; i < n; i++){
				int kkk = k%round[i];
				ttmp = i+1;
			//	kkk--;
				while(kkk>0){
					ttmp = a[ttmp-1];
					kkk--;
			//		cout<<kkk<<endl;
				}
				textTemp[ttmp-1] = text[i];
			}
		//	k--;
			for(int i = 0; i < n; i++){
				text[i] = textTemp[i];
			}
		//	}
			for(int i = 0; i < n; i++){
					cout << text[i];
			}
	//		cout<<text;
			cout << endl;
			cin >> k;
		}
		cout << endl;
		cin >> n;
	}
}

参考：

http://www.cnblogs.com/ns517/archive/2009/03/04/1402951.html

http://blog.youkuaiyun.com/jw72jw/article/details/5810120

http://www.cppblog.com/csu-yx-2013/archive/2011/11/10/159934.html