ProdusXL

#include <fstream>
#define N 111
using namespace std;
typedef int Huge[N];

void Nr_Huge(Huge X,int n) /// X <- n
{
    int i=0;
    X[0]=0;
    if(n==0)
        X[0]=1,X[1]=0;
    else
        while(n)
            ++X[0],X[++i]=n%10,n/=10;
}

void MultHuge(Huge A,Huge B) /// A <- A x B
{
    if(B[0]==1&&B[1]==0) /// Verific daca al doilea numar este 0
    {
        A[0]=1;
        A[1]=0;
        return;
    }
    int i,j,T=0;
    Huge C;
    C[0]=A[0]+B[0]-1;
    for(i=1;i<=A[0]+B[0];)
        C[i++]=0;
    for(i=1;i<=A[0];++i)
        for(j=1;j<=B[0];++j)
            C[i+j-1]+=A[i]*B[j];
    for(i=1;i<=C[0];++i)
        T=(C[i]+=T)/10,C[i]%=10;
    if(T)
        C[++C[0]]=T;
    for(i=0;i<=C[0];++i)
        A[i]=C[i];
}

int main()
{
    int n;
    Huge nr_mare,nr_mic;
    ifstream f("produsxl.in");
    f>>n;
    for(int i=1;i<=n;++i)
        f>>nr_mare[n-i+1];
    nr_mare[0]=n;
    int nr;
    f>>nr;
    f.close();
    Nr_Huge(nr_mic,nr);
    MultHuge(nr_mare,nr_mic);
    ofstream g("produsxl.out");
    for(int i=nr_mare[0];i>0;--i)
        g<<nr_mare[i];
    g<<'\n';
    g.close();
    return 0;
}