1/n循环节长度

ACM模版

1/n循环节长度

/* *  求1/i的循环节长度的最大值，i<=n */const int MAXN = 1005;int res[MAXN];  //  循环节长度int main(){    memset(res, 0, sizeof(res));    int i, temp, j, n;    for (temp = 1; temp <= 1000; temp++)    {        i = temp;        while (i % 2 == 0)        {            i /= 2;        }        while (i % 5 == 0)        {            i /= 5;        }        n = 1;        for (j = 1; j <= i; j++)        {            n *= 10;            n %= i;            if (n == 1)            {                res[temp] = j;                break;            }        }    }    int max_re;    while (cin >> n)    {        max_re = 1;        for (i = 1; i <= n; i++)        {            if (res[i] > res[max_re])            {                max_re = i;            }        }        cout << max_re << endl;    }    return 0;}