Cod sursa(job #2538913)

Utilizator AlexPascu007Pascu Ionut Alexandru AlexPascu007 Data 5 februarie 2020 12:35:45
Problema Al k-lea termen Fibonacci Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1 kb
#include <bits/stdc++.h>
#define mod 666013
using namespace std;
ifstream fin("kfib.in");
ofstream fout("kfib.out");
long long k,sol;
long long a[2][2]={{1,1},{1,0}}, r[2][2]={{1,0},{0,1}}, b[2][2];
void inmultire(long long a[2][2],long long b[2][2],long long c[2][2]) {
    for (long long i=0;i<2;i++)
        for (long long j=0;j<2;j++) {
            c[i][j]=0;
            for (long long k=0;k<2;k++) {
                c[i][j]+=a[i][k]*b[k][j];
                c[i][j]%=mod;
            }
        }
}
void copiere(long long a[2][2],long long b[2][2]) {
    for (long long i=0;i<2;i++)
        for (long long j=0;j<2;j++)
            a[i][j]=b[i][j];
}
int main() {
    fin>>k;
    if (k<=2) {
        fout<<1;
        return 0;
    }
    k-=2;
    while (k) {
        if (k%2==1) {
            inmultire(r,a,b);
            copiere(r,b);
        }
        inmultire(a,a,b);
        copiere(a,b);
        k/=2;
    }
    sol=r[0][0]+r[0][1];
    fout<<sol%mod;
    return 0;
}