counterase

#include <bits/stdc++.h>
using namespace std;

short int Divide(short int *A) /// A <- A/X si intoarce A%X
{
    short int R=0;
    for(short int i=A[0];i;--i,R%=2)
        R=R*10+A[i],A[i]=R/2;
    while(!A[A[0]]&&A[0]>1)
        --A[0];
    return R;
}

void MultHuge(short int *A,short int *B) /// A <- A x B
{
    short int C[1001];
    short int T=0;
    C[0]=A[0]+B[0];
    for(short int i=1;i<=C[0];++i)
        C[i]=0;
    --C[0];
    for(short int i=1;i<=A[0];++i)
        for(short int j=1;j<=B[0];++j)
            C[i+j-1]+=A[i]*B[j];
    for(short int i=1;i<=C[0];++i)
        T+=C[i],C[i]=T%10,T/=10;
    if(T)
        C[++C[0]]=T;
    for(short int i=0;i<=C[0];++i)
        A[i]=C[i];
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    string str;
    cin>>str;  /// citesc numarul
    short int n=str.length(),X[501];
    X[0]=0;
    for(short int i=n-1;i>=0;--i) /// pun numarul invers in vectorul X
        X[++X[0]]=str[i]-'0';
    unsigned long long int cnt1=0;
    while(X[0]>1) /// Cat timp mai am ce imparti impart la 2
    {
        short int r=Divide(X);
        if(r) /// numar resturile de 1
            ++cnt1;
    }
    if(X[0]==1) /// Caz perticular (X[1]!=0)
        if(X[1]>1)
            {
                while(X[1]>=1)
                {
                    if(X[1]%2) /// adica restul e 1
                        ++cnt1;
                    X[1]/=2;
                }
            }
    X[0]=X[1]=1; /// acum calculez puterile lui 2 la cnt1
    short int A[2000];
    A[0]=1,A[1]=2;
    while(cnt1) /// Calculez 2^cnt1 (exponentiere logaritmica)
    {
        if(cnt1%2)
            MultHuge(X,A); /// X <- X*A (Initial A e 2)
        MultHuge(A,A); /// A <- AxA
        cnt1/=2;
    }
    for(short int i=X[0];i>=1;--i)
        cout<<X[i];
    cout<<'\n';
    return 0;
}