Cod sursa(job #3243191)

Utilizator AnaMateiAna Matei AnaMatei Data 16 septembrie 2024 14:52:20
Problema Al k-lea termen Fibonacci Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.85 kb
#include <iostream>
#include <fstream>

using namespace std;

int const mod=666013;

ifstream f("kfib.in");
ofstream g("kfib.out");

void inmultireMat(int mat1[][2], int mat2[][2])
{
    long long rez[2][2]= {0};
    int i, j, k;
    for(i=0; i<2; i++)
        for(j=0; j<2; j++)
            for(k=0; k<2; k++)
                rez[i][j]+=mat1[i][k]*mat2[k][j];
    for(i=0; i<2; i++)
        for(j=0; j<2; j++)
            mat1[i][j]=rez[i][j]%mod;
}


int expLog(long long exp)
{
    int rez[2][2]= {{1, 0},{0, 1}}, matFibo[2][2]= {{1, 1}, {1, 0}};;
    while(exp>0)
    {
        if(exp%2==1)
            inmultireMat(rez, matFibo);
        inmultireMat(matFibo, matFibo);
        exp/=2;
    }
    return rez[0][0];
}

int main()
{
    int k;
    f>>k;
    g<<expLog(k-1)<<'\n';
    f.close();
    g.close();
    return 0;
}