不知道无限循环小数怎么化分数的直接百度
知道直接暴力枚举循环的位数即可
#include<iostream> #include<cmath> #include<cstdio> #include<cstdlib> #include<cstring> #include<iomanip> #include<assert.h> #include<ctime> #include<vector> #include<list> #include<map> #include<set> #include<sstream> #include<stack> #include<queue> #include<string> #include<bitset> #include<algorithm> using namespace std; #define me(s) memset(s,0,sizeof(s)) #define mp make_pair #define pb push_back #define all(x) (x).begin(),(x).end() #define F first #define S second #define pf printf #define sf scanf #define Di(x) int x;scanf("%d",&x) #define in(x) inp(x) #define in2(x,y) inp(x),inp(y) #define in3(x,y,z) inp(x),inp(y),inp(z) #define ins(x) scanf("%s",x) #define ind(x) scanf("%lf",&x) #define IO ios_base::sync_with_stdio(0);cin.tie(0) #define READ freopen("C:/Users/ASUS/Desktop/in.txt","r",stdin) #define WRITE freopen("C:/Users/ASUS/Desktop/out.txt","w",stdout) template<class T> void inp(T &x) {//读入优化 char c = getchar(); x = 0; for (; (c < 48 || c>57); c = getchar()); for (; c > 47 && c < 58; c = getchar()) { x = (x << 1) + (x << 3) + c - 48; } } typedef pair <int, int> pii; typedef long long ll; typedef unsigned long long ull; const int inf = 0x3f3f3f3f; const int mod = 1e9 + 7; const double pi = acos(-1.0); const double eps = 1e-15; string s; ull gcd(ull a,ull b) {return b==0?a:gcd(b,a%b);} ull Pow(int x){ ull ret=1; for(int i=1;i<=x;i++) ret*=10; return ret; } int main(){ //READ; //WRITE; while(cin>>s){ if(s=="0") break; s=s.substr(2,s.size()-5); //cout<<s<<endl; int len=s.size(); ull n=atoi(s.c_str()); if(!n) { printf("0/1\n"); continue; } ull minx=0,miny=inf; for(int i=1;i<=len;i++){ ull x=n-atoi(s.substr(0,len-i).c_str()); ull y=Pow(len)-Pow(len-i); ull d=gcd(x,y); x/=d;y/=d; if(y<miny) { miny=y; minx=x; } } cout<<minx<<"/"<<miny<<endl; } }