Wikioi1281Xn数列(随机数产生器)

 

题目描述 Description

给你6个数，m, a, c, x0, n, g

Xn+1 = ( aXn + c ) mod m，求Xn

m, a, c, x0, n, g<=10^18

输入描述 Input Description

一行六个数 m, a, c, x0, n, g

输出描述 Output Description

输出一个数 Xn mod g

样例输入 Sample Input

11 8 7 1 5 3

样例输出 Sample Output

2

数据范围及提示 Data Size & Hint

int64按位相乘可以不要用高精度。

这尼玛都没个伪装啊

 1 #include <iostream>
 2 #include <cstdlib>
 3 #include <cstdio>
 4 #include <cstring>
 5 #include <algorithm>
 6 using namespace std;
 7 long long m, a, c, x0, n, g;
 8 template <int A, int B>
 9 struct matrix
10 {
11     long long v[A][B];
12     matrix(long long r = 0)
13     {
14         memset(v, 0, sizeof(v));
15         for (int i = 0; i < A && i < B; i++)
16             v[i][i]    = r;
17     }
18     matrix(long long a[A][B])
19     {
20         memcpy(v, a, sizeof(a));
21     }    
22 };
23 inline long long quickadd(long long a, long long b)
24 {
25     long long ans = 0;
26     for (; b; b >>= 1)
27     {
28         if (b & 1) ans = (ans + a) % m;
29         a = (a + a) % m;
30     }
31     return ans;
32 }
33 template <int A, int B, int C>
34 matrix <A, C> operator * (const matrix <A, B> &a, const matrix <B, C> &b)
35 {
36     matrix <A, C> ans;
37     for (int i = 0; i < A; i++)
38         for (int j = 0; j < C; j++)
39         {
40             long long v = 0;
41             for (int k = 0; k < B; k++)
42                 v += quickadd(a.v[i][k], b.v[k][j]);
43             ans.v[i][j] = (v % m + m) % m;
44         }
45     return ans;
46 }
47 template <int A>
48 matrix <A, A> power(const matrix<A, A> &a, long long b)
49 {
50     matrix <A, A> ans = 1;
51     for (matrix<A, A> i = a; b; b >>= 1)
52     {
53         if (b & 1) ans = ans * i;
54         i = i * i;
55     }
56     return ans;
57 }
58 
59 matrix <2, 2> w;
60 matrix <1, 2> x;
61 int main()
62 {
63     scanf("%lld%lld%lld%lld%lld%lld", &m, &a, &c, &x0, &n, &g);
64     w.v[0][0] = a;
65     w.v[1][0] = w.v[1][1] = 1;
66     x.v[0][0] = x0;
67     x.v[0][1] = c;
68     printf("%lld\n", (x * power(w, n)).v[0][0] % g);
69     return 0;
70 }