Cod sursa(job #2715520)

Utilizator Horis21Horia Radu Horis21 Data 3 martie 2021 19:30:23
Problema Al k-lea termen Fibonacci Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.86 kb
#include <iostream>
#include <fstream>
#include <string.h>

using namespace std;


ifstream in("kfib.in");
ofstream out("kfib.out");
int a[2][2];
int sol[2][2];
const int MOD=666013;

void multiplication(int a[2][2],int b[2][2])
{
    int ans[2][2];
    memset(ans,0,16);
    for(int i=0; i<2; i++)
    {
        for(int j=0; j<2; j++)
        {
            for(int k=0; k<2; k++)
            {
                ans[i][j]=(ans[i][j]+1LL*a[i][k]*b[k][j])%MOD;
            }
        }
    }
    memcpy(a,ans,16);
}
void logpow(int p)
{
    while(p)
    {
        if(p%2) multiplication(sol,a);
        p/=2;
        multiplication(a,a);
    }
}
int main()
{
    int n;
    in>>n;
    a[0][0]=0;
    a[0][1]=a[1][0]=a[1][1]=1;
    sol[1][0]=sol[1][1]=0;
    sol[0][0]=sol[0][1]=1;
    logpow(n-1);
    out<<sol[0][0];
    return 0;
}