【bzoj4002】[JLOI2015]有意义的字符串数论+矩阵乘法

#include 
#include 
#include 
#define mod 7528443412579576937ull
using namespace std;
typedef unsigned long long ull;
ull qmul(ull x , ull y)
{
    ull ans = 0;
    while(y)
    {
        if(y & 1) ans = (ans + x) % mod;
        x = (x + x) % mod;
        y >>= 1;
    }
    return ans;
}
struct matrix
{
    int n , m;
    ull num[2][2];
    matrix()
    {
        n = m = 0 , memset(num , 0 , sizeof(num));
    }
    matrix operator*(matrix a)
    {
        matrix t;
        t.n = n , t.m = a.m;
        int i , j , k;
        for(i = 0 ; i >= 1;
    }
    return t;
}
int main()
{
    ull b , d , n , x , y , ans;
    scanf("%llu%llu%llu" , &b , &d , &n);
    x = b , y = (d - b * b) / 4;
    A.n = 1 , A.m = 2 , A.num[0][0] = 2 , A.num[0][1] = b;
    B.n = 2 , B.m = 2 , B.num[0][1] = y , B.num[1][0] = 1 , B.num[1][1] = x;
    ans = (A * qpow(B , n)).num[0][0];
    if(y && n % 2 == 0) ans = (ans + mod - 1) % mod;
    printf("%llu\n" , ans);
    return 0;
}