hdu 2276 矩阵 二分

#include <iostream>
#include <cstring>
using namespace std;

const int MAXN = 110;
int X, mod = 2;
int hash[MAXN][MAXN];
int sum[MAXN][MAXN];
int a[MAXN][MAXN];
int result[MAXN];
int len;

int matrix_binary()
{
    int n = len;
    long i, j, t, p, k;
    memset(sum, 0, sizeof(sum));
    memset(hash, 0, sizeof(hash));
    for (i = 0; i < n; i++)
    {
        sum[i][i] = 1;
        hash[i][i] = 1;
        sum[(i + n - 1) % n][i] = 1;
    }
    for (p = X; p > 1;)
    {
        if (p & 1)
        {
            for (i = 0; i < n; i++)
            {
                for (j = 0; j < n; j++)
                {
                    for (t = 0, k = 0; k < n; k++)
                    {
                        t += hash[i][k] * sum[k][j];
                    }
                    a[i][j] = t % mod;
                }
            }
            for (i = 0; i < n; i++)
            {
                for (j = 0; j < n; j++)
                {
                    hash[i][j] = a[i][j];
                }
            }
            p--;
        }
        else
        {
            for (i = 0; i < n; i++)
            {
                for (j = 0; j < n; j++)
                {
                    for (t = 0, k = 0; k < n; k++)
                    {
                        t += sum[i][k] * sum[k][j];
                    }
                    a[i][j] = t % mod;
                }
            }
            for (i = 0; i < n; i++)
            {
                for (j = 0; j < n; j++)
                {
                    sum[i][j] = a[i][j];
                }
            }
            p = p >> 1;
        }
    }
    for (i = 0; i < n; i++)
    {
        for (j = 0; j < n; j++)
        {
            for (t = 0, k = 0; k < n; k++)
            {
                t += sum[i][k] * hash[k][j];
            }
            a[i][j] = t % mod;
        }
    }
    return 0;
}

int main()
{
    char c[110];
    while (scanf("%d", &X) != EOF)
    {
        scanf("%s", c);
        len = strlen(c);
        int i, j;
        for (i = 0; i < len; ++i)
        {
            if (c[i] == '0')
            {
                result[i] = 0;
            }
            else
            {
                result[i] = 1;
            }
        }

        matrix_binary();
        //for (i = 0; i < len; ++i)
        //{
        //    for (j = 0; j < len; ++j)
        //    {
        //        printf("%d ", a[i][j]);
        //    }
        //    puts("");
        //}
        int tmp[MAXN];
        for (i = 0; i < len; ++i)
        {
            int t = 0;
            for (j = 0; j < len; ++j)
            {
                t += result[j]*a[j][i];
            }
            tmp[i] = t % mod;
        }
        for (i = 0; i < len; ++i)
        {
            printf("%d", tmp[i]);
        }
        puts("");
    }
    return 0;
}