bzoj 4002: [JLOI2015]有意义的字符串

时间:2023-03-08 17:43:20

  这个题。。。

  

 #include <bits/stdc++.h>
#define rep(i, a, b) for (int i = a; i <= b; i++)
#define drep(i, a, b) for (int i = a; i >= b; i--)
#define REP(i, a, b) for (int i = a; i < b; i++)
#define mp make_pair
#define pb push_back
#define clr(x) memset(x, 0, sizeof(x))
#define xx first #define yy second
using namespace std;
typedef pair<int, int> pii;
typedef unsigned long long ll;
const int inf = 0x3f3f3f3f;
const ll INF = 0x3f3f3f3f3f3f3f3fll;
//************************************************ const ll mod = 7528443412579576937LL;
ll mul(ll base, ll num) {
ll ret();
while (num) {
if (num & ) ret = (ret + base) % mod;
base = (base + base) % mod;
num >>= ;
}
return ret;
}
struct matrix {
ll s[][]; matrix () { clr(s); }
matrix operator * (const matrix &B) const {
matrix A = *this, C;
rep(i, , ) rep(j, , ) rep(k, , )
C.s[i][j] = (C.s[i][j] + mul(A.s[i][k], B.s[k][j]) % mod) % mod;
return C;
}
} ori; matrix POW(matrix base, ll num) {
matrix ret = ori;
while (num) {
if (num & ) ret = ret * base;
base = base * base;
num >>= ;
}
return ret;
} int main() {
ll b, d, n; scanf("%llu%llu%llu", &b, &d, &n);
ll a = b, c = (d - b * b) >> ;
ori.s[][] = ori.s[][] = ;
matrix base; base.s[][] = a, base.s[][] = c, base.s[][] = ;
matrix ans;
ans.s[][] = , ans.s[][] = b;
ans = ans * POW(base, n);
if (d != b * b && n % == ) ans.s[][]--;
printf("%llu\n", ans.s[][]);
}