poj1047 Round and Round We Go

Description

Input

Output

Sample Input

142857
142856
142858
01
0588235294117647

Sample Output

142857 is cyclic
142856 is not cyclic
142858 is not cyclic
01 is not cyclic
0588235294117647 is cyclic

题意：给出一个字符串，如果这个字符串分别用1,2,...,len去乘，最终得到的结果还是由这个字符串的字符组成的，那么它是cyclic；

解题思路：给出的数*（len+1）=9...9（len个）,那么这个数是cyclic

参考代码：

#include <iostream>
#include <string.h>
using namespace std;
char s[100];
int a[100];
int main(){
	while (cin>>s){
		int len=strlen(s);
		memset(a,0,sizeof(a));
		int k=0,left=0;
		for (int i=len-1;i>=0;i--){
			int ans=(s[i]-'0')*(len+1)+left;
			a[k++]=ans%10;
			left=ans/10;
		}
		while (left!=0){
			a[k++]=left%10;
			left/=10;
		}
		int flag=0;
		for (int i=0;i<k;i++){
			if (a[i]!=9){
				flag=1;
				break;
			}
		}
		if (flag==1)
			cout<<s<<" is not cyclic"<<endl;
		else
			cout<<s<<" is cyclic"<<endl;
	}
	return 0;
}

poj1047 Round and Round We Go

原文：http://blog.csdn.net/codeforcer/article/details/43576701