Cod sursa(job #2605197)

Utilizator BogdanRuleaBogdan Rulea BogdanRulea Data 24 aprilie 2020 16:45:52
Problema Al k-lea termen Fibonacci Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.93 kb
#include <fstream>
#include <cstring>
using namespace std;
ifstream cin("kfib.in");
ofstream cout("kfib.out");

#define mod 666013
int  sol[3][3],mat[3][3];
void mult(int a[][3],int b[][3],int c[][3])
{
    for(int i=0; i<2; i++)
        for(int j=0; j<2; j++)
            for(int k=0; k<2; k++)
                c[i][j]=(c[i][j]+1LL* a[i][k] * b[k][j])%mod;
}
void lgput(int  p,int m[][3])
{
    int c[3][3],aux[3][3];
    memcpy(c,mat,sizeof(mat));
    m[0][0]=m[1][1]=1;
    for(int i=0; (1<<i)<=p; i++)
    {
        if(p & (1<<i))
        {
            memset(aux,0,sizeof(aux));
            mult(m,c,aux);
            memcpy(m,aux,sizeof(aux));
        }
        memset(aux,0,sizeof(aux));
        mult(c,c,aux);
        memcpy(c,aux,sizeof(c));
    }
}
int main()
{
    int n;
    mat[0][0]=0;
    mat[0][1]=1;
    mat[1][1]=mat[1][0]=1;
    cin>>n;
    lgput(n-1,sol);
    cout<<sol[1][1];
    return 0;
}