Cod sursa(job #2591964)

Utilizator nicolaefilatNicolae Filat nicolaefilat Data 31 martie 2020 19:06:59
Problema Al k-lea termen Fibonacci Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.52 kb
#include <iostream>
#include <fstream>

const int MOD = 666013;

using namespace std;

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

int n,fibo[2][2] = {{0,1},{1,1}};
int raspuns[2][2] = {{1,0},{0,1}};

void inmulteste(int a[2][2],int b[2][2]){
//    a[0][0] = (1ll * a[0][0] * b[0][0] % MOD + 1ll * a[0][1] * b[1][0] % MOD) % MOD;
//    a[0][1] = (1ll * a[0][0] * b[0][1] % MOD + 1ll * a[0][1] * b[1][1] % MOD) % MOD;
//    a[1][0] = (1ll * a[1][0] * b[0][0] % MOD + 1ll * a[1][1] * b[1][0] % MOD) % MOD;
//    a[1][1] = (1ll * a[1][0] * b[0][1] % MOD + 1ll * a[1][1] * b[1][1] % MOD) % MOD;
    int c[2][2];
    for(int i = 0; i < 2; i++){
        for(int j = 0; j < 2; j++){
            c[i][j] = 0;
            for(int k = 0; k < 2; k++)
                c[i][j] = (1ll * a[i][k] * b[k][j] + c[i][j]) % MOD;
        }
    }
    for(int i = 0; i < 2; i++)
        for(int j = 0; j < 2; j++)
            a[i][j] = c[i][j];
}
void afis(){
    for(int i = 0; i < 2; i++){
        //for(int j = 0; j < 2; j++)
            //cout<<fibo
    }
}
void exponentiere(int exponent){

    while(exponent > 0){
        if(exponent % 2 == 0){
            inmulteste(fibo,fibo);
        }else{
            inmulteste(raspuns,fibo);
            inmulteste(fibo,fibo);
        }
        exponent /= 2;
    }
    for(int i = 0; i < 2; i++)
        for(int j = 0; j < 2; j++)
            fibo[i][j] = raspuns[i][j];

}

int main()
{
    in>>n;
    exponentiere(n);
    out<<fibo[1][0] % MOD;
    return 0;
}