#553. 【2018年6月多校联训B组day10测试一】数列

https://sjzezoj.com/submission/20151

S2OJ/553/553.cpp

@@ -0,0 +1,76 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+const unsigned long long mod = 1e18;
+
+unsigned long long n;
+
+unsigned long long mul(unsigned long long a, unsigned long long b) {
+    unsigned long long res = 0;
+    while (b) {
+        if (b & 1) res = (res + a) % mod;
+        a = (a << 1) % mod;
+        b >>= 1;
+    }
+    return res;
+}
+
+struct matrix {
+    unsigned long long f[4][4];
+
+    matrix() {
+        memset(f, 0x00, sizeof(f));
+    }
+
+    void init() {
+        for (int i = 0; i < 4; i++) {
+            f[i][i] = 1;
+        }
+    }
+
+    matrix operator*(matrix b) {
+        matrix res;
+        for (int i = 0; i < 4; i++) {
+            for (int j = 0; j < 4; j++) {
+                for (int k = 0; k < 4; k++) {
+                    res[i][j] = (res[i][j] + mul(f[i][k], b[k][j])) % mod;
+                }
+            }
+        }
+        return res;
+    }
+
+    matrix operator^(unsigned long long b) {
+        matrix t;
+        t.init();
+        while (b) {
+            if (b & 1) t = t * *this;
+            *this = *this * *this;
+            b >>= 1;
+        }
+        return t;
+    }
+
+    unsigned long long* operator[](int x) {
+        return f[x];
+    }
+} a, b;
+
+int main() {
+    cin >> a[0][2] >> a[0][1] >> a[0][0];
+    cin >> b[0][0] >> b[1][0] >> b[2][0];
+    cin >> a[0][3] >> n;
+    b.f[0][1] = b.f[1][2] = b.f[3][0] = b.f[3][3] = 1;
+    if (n <= 2) {
+        cout << a[0][2 - n] << endl;
+        exit(0);
+    }
+    int len = 0;
+    a = a * (b ^ (n - 2));
+    for (int i = 0; i < 18 - to_string(a[0][0]).size(); i++) {
+        cout << 0;
+    }
+    cout << a[0][0] << endl;
+    return 0;
+}