循环小数

poj1930

#include<stdio.h>
#include<string.h>
#include<iostream>
#include<math.h>
#include<algorithm>
using namespace std;
typedef unsigned long long ll;
#define SIS std::ios::sync_with_stdio(false),cin.tie(0),cout.tie(0);

const ll MAXN=45000;
const int MOD=10000000;

ll gcd(ll a,ll b){
	if(b==0)return a;
	return gcd(b,a%b);
}

int main(){
	char str[100];
	int num,k,all,a,b,i,j,mina,minb,l;
	while(cin>>str&&strcmp(str,"0")){
		mina=minb=1000000000;
		for(i=2,all=0,l=0;str[i]!='.';i++){
			all=all*10+str[i]-48;
			l++;
		}
		for(num=all,k=1,i=1;i<=l;i++){
			num/=10;
			k*=10;
			a=all-num;
			b=(int)pow(10.0,l-i)*(k-1);
			j=gcd(a,b);
			if(b/j<minb){
				mina=a/j;	minb=b/j;
			}
		}
		cout<<mina<<'/'<<minb<<endl;
	}
	return 0;
}

来源：CSDN

作者：Chemin Du Retour

链接：https://blog.csdn.net/weixin_45535964/article/details/104522594