ngồi code 2 tiếng đồng hồ T_T

#include <bits/stdc++.h>
#define ll long long
#define str string
using namespace std;
#define mod 1000000007
ll ucln(ll a,ll b)
{
    if(b==0) return a;
    return ucln(b,a%b);
}
int main()
{
    str n;
    ll a,b,c,d;
    cin>>n;
    ll i,t,dem0=0,dem9=0;
    for(i=0;i<n.length();i++)
    {
        if(n[i]=='.')
        {
            a=n[0]-'0';
             for(ll j=1;j<i;j++)
             {
                 a=a*10+n[j]-'0';
             }
             t=i+1;
        }
    }
    if(i==n.length()-1)
    {
        cout<<n;
    }
    else
    {
        if(n[t]=='(')
        {
            dem0=0;
            b=0;
            c=n[t+1]-'0';
            dem9=1;
            for(i=t+2;i<n.size()-1;i++)
            {
                c=c*10+n[i]-'0';
                dem9++;
            }
        }
        else
        {
            for(i=t;i<n.length();i++)
            {
                if(n[i]=='(')
                {
                    b=n[t]-'0';
                    dem0=1;
                    for(ll j=t+1;j<i;j++)
                    {
                        b=b*10+n[j]-'0';
                        dem0++;
                    }
                    n.erase(i,1);
                    n.erase(n.length()-1,1);
                    c=n[t]-'0';
                    dem9=1;
                    for(ll j=t+1;j<n.length();j++)
                    {
                        c=c*10+n[j]-'0';
                        dem9++;
                    }
                }
            }
        }
        if(i==n.length()&&n[t]!='(')
        {
            b=n[t]-'0';
            dem0=1;
            for(i=t+1;i<n.length();i++)
            {
                b=b*10+n[i]-'0';
                dem0++;
            }
            c=pow(10,dem0);
            b=b+a*c;
            d=ucln(b,c);
            b/=d;
            c/=d;
            cout<<b<<"/"<<c;
        }
        else
        {
            dem9-=dem0;
            d=0;
            for(i=0;i<dem9;i++)
            {
                d=d*10+9;
            }
            d=d*pow(10,dem0);
            c=c-b;
            c=c+a*d;
            ll e=ucln(c,d);
            d/=e;
            c/=e;
            cout<<c<<"/"<<d;
        }
    }
}

#include<bits/stdc++.h>
#define ll long long
#define ios ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#pragma GCC optimize("O3","unroll-loops")
#pragma GCC optimize("Ofast")
using namespace std;
int main() {
    ios
    string d;
    cin>>d;
    ll n,m;
    ll f[2]={0,1};
    ll p=d.find('.');
    string i=d.substr(0,p);
    ll ip=stoi(i);
    if(p==string::npos) {
        f[0]=ip;
        f[1]=1;
    }
    else
    {
        string fp=d.substr(p+1);
        ll rs=fp.find('(');
        if(rs==string::npos)
        {
            ll fl=fp.size();
            ll fn=stoll(fp);
            m=pow(10,fl);
            n=ip*m+fn;
        }
        else
        {
            string nr=fp.substr(0,rs);
            string r=fp.substr(rs+1,fp.find(')')-rs-1);
            ll nrl=nr.size();
            ll rl=r.size();
            ll nrn=0;
            if(!nr.empty()) nrn=stoll(nr);
            ll rn=stoll(r);
            ll dnr=pow(10,nrl);
            ll dr=pow(10,rl)-1;
            n=ip*dnr*dr+nrn*dr+rn;
            m=dnr*dr;
        }
        ll div=__gcd(n,m);
        n/=div;
        m/=div;
        f[0]=n;
        f[1]=m;
    }
    cout<<f[0]<<"/"<<f[1];
    return 0;
}