Cod sursa(job #2580428)

Utilizator AlexNeaguAlexandru AlexNeagu Data 13 martie 2020 16:56:24
Problema Al k-lea termen Fibonacci Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.56 kb
#include <bits/stdc++.h>
#define x first
#define y second
#define pb push_back
using namespace std;
typedef long long ll;
ifstream in("kfib.in");
ofstream out("kfib.out");
const int MOD = 666013;
int z[3][3], a[2][3], ans[3][3], aux[3][3];
void init_aux() {
  for (int i = 1; i <= 2; i++) {
    for (int j = 1; j <= 2; j++) {
      aux[i][j] = 0;
    }
  }
}
int add(int x, int y) {
  x += y;
  if (x >= MOD) {
    x -= MOD;
  }
  return x;
}
int mul(int a, int b) {
  return (1ll * a * b) % MOD;
}
void prod(int x[3][3], int y[3][3]) {
  init_aux();
  for (int i = 1; i <= 2; i++) {
    for (int j = 1; j <= 2; j++) {
      for (int k = 1; k <= 2; k++) {
        aux[i][j] = add(aux[i][j], mul(x[i][k], y[k][j]));
      }
    }
  }
}
void pow(int exp) {
  while(exp) {
    if (exp & 1) {
      prod(ans, z);
      for (int i = 1; i <= 2; i++) {
        for (int j = 1; j <= 2; j++) {
          ans[i][j] = aux[i][j];
        }
      }
    }
    prod(z, z);
    for (int i = 1; i <= 2; i++) {
      for (int j = 1; j <= 2; j++) {
        z[i][j] = aux[i][j];
      }
    }
    exp /= 2;
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  int n;
  in >> n;
  z[1][2] = z[2][1] = z[2][2] = 1;
  a[1][1] = a[1][2] = 1;
  ans[1][1] = ans[2][2] = 1;
  if (n == 1) {
    out << "1\n";
    return 0;
  }
  pow(n - 1);
  init_aux();
  for (int i = 1; i <= 2; i++) {
    for (int k = 1; k <= 2; k++) {
      aux[1][i] = add(aux[1][i], mul(a[1][k], ans[k][i]));
    }
  }
  out << aux[1][1] << '\n';
  return 0;
}