Cod sursa(job #82104)

Utilizator DastasIonescu Vlad Dastas Data 5 septembrie 2007 18:34:32
Problema Patrate2 Scor 80
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.11 kb
#include <iostream>


const int maxn = 2000;

FILE *in = fopen("patrate2.in","r"), *out = fopen("patrate2.out","w");

int N;
short H[maxn];
short B[maxn];

void mul(short A[], int B)
{
    int i, t = 0;
    for (i = 1; i <= A[0] || t; i++, t /= 10)
        A[i] = (t += A[i] * B) % 10;
    A[0] = i - 1;
}

short C[maxn];
void mulmare(short A[], short B[])
{
    int i, j, t;
    for (i = 1; i <= A[0]; i++)
    {
        for (t=0, j=1; j <= B[0] || t; j++, t/=10)
            C[i+j-1]=(t+=C[i+j-1]+A[i]*B[j])%10;
        if (i + j - 2 > C[0]) C[0] = i + j - 2;
    }
}

int main()
{
    fscanf(in, "%d", &N);


    H[0] = 1;
    H[1] = 2;

    B[0] = 1;
    B[1] = 1;

    int end = N*N;


    for ( int i = 1; i < end; ++i )
        mul(H, 2);

    for ( int i = 2; i <= N; ++i )
        mul(B, i);


    if ( B[0] == 1 )
        mul(H, B[1]);
    else
        mulmare(H, B);

    if ( B[0] == 1 )
        for ( int i = H[0]; i; --i )
            fprintf(out, "%d", H[i]);
    else
        for ( int i = C[0]; i; --i )
            fprintf(out, "%d", C[i]);

	return 0;
}