Cod sursa(job #3191799)

Utilizator NeacsaDenisDenis Neacsa NeacsaDenis Data 10 ianuarie 2024 17:49:01
Problema Al k-lea termen Fibonacci Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.02 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream f("kfib.in");
ofstream g("kfib.out");

const int MOD = 666013;
int matFibInit[2][2] = {{1, 1}, {1, 0}}, matFib[2][2];

void mulMat(int A[][2], int B[][2])
{
    long long C[2][2];
    for(int i = 0; i < 2; i++)
        for(int j = 0; j < 2; j++)
        {
            C[i][j] = 0;
            for(int p = 0; p < 2; p++)
                C[i][j] += 1LL * A[i][p] * B[p][j];
        }
    for(int i = 0; i < 2 ; i++)
        for(int j = 0; j < 2 ; j++)
            A[i][j] = C[i][j] % MOD;
}

void calcul(int k)
{
    for(int i = 0; i < 2 ; i++)
        matFib[i][i] = 1;
    while(k > 0)
    {
        if(k % 2 == 0)
        {
            mulMat(matFibInit, matFibInit);
            k /= 2;
        }
        else
        {
            mulMat(matFib, matFibInit);
            k--;
        }
    }
}

int main()
{
    int K;
    f >> K;
    calcul(K);
    g << matFib[0][1];
    f.close();
    g.close();
    return 0;
}