Cod sursa(job #956346)

Utilizator dr_personalityEftime Andrei Horatiu dr_personality Data 2 iunie 2013 21:41:21
Problema Al k-lea termen Fibonacci Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.09 kb
#include <cstdio>
#include <cstring>
#define mod 666013
 
using namespace std;
 
int N, i,b;
int MAT[3][3], SOL[3][3];
 
inline void mult(int A[][3], int B[][3], int C[][3]) {
    int i, j, k;
    for (i = 0; i < 2; i++)
        for (j = 0; j < 2; j++)
            for (k = 0; k < 2; k++) 
                C[i][j] = (C[i][j] + 1LL * A[i][k] * B[k][j]) % b;
             
}
 
inline void lg_power(int P, int M[][3]) {
    int C[3][3], AUX[3][3], i;
     
    memcpy(C, MAT, sizeof(MAT));
    M[0][0] = M[1][1] = 1;
 
    for (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() {
    freopen("kfib.in", "r", stdin);
    freopen("kfib.out", "w", stdout);
 
    scanf("%d", &N);
 
    MAT[0][0] = 0; MAT[0][1] = 1; MAT[1][0] = 1; MAT[1][1] = 1;
 
    lg_power(N - 1, SOL);
 
    printf("%d\n", SOL[1][1]);
 
    return 0;
}