矩阵经典题目六：poj 3070 Fibonacci

#include <stdio.h>
#include <iostream>
#include <map>
#include <set>
#include <list>
#include <stack>
#include <vector>
#include <math.h>
#include <string.h>
#include <queue>
#include <string>
#include <stdlib.h>
#include <algorithm>
#define LL long long
#define _LL __int64
#define eps 1e-12
#define PI acos(-1.0)
#define C 240
#define S 20
using namespace std;

const int maxn = 110;

struct matrix
{
int mat[3][3];
void init()
{
memset(mat,0,sizeof(mat));
mat[1][1] = mat[2][2] = 1;
}
}a;

matrix mul(matrix a, matrix b)
{
matrix res;
memset(res.mat,0,sizeof(res.mat));
for(int i = 1; i <= 2; i++)
{
for(int k = 1; k <= 2; k++)
{
if(a.mat[i][k] == 0) continue;
for(int j = 1; j <= 2; j++)
{
int t = a.mat[i][k]*b.mat[k][j];
res.mat[i][j] = (res.mat[i][j] + t)%10000;
}
}
}
return res;
}

matrix pow(matrix a, int n)
{
matrix res;
res.init();

while(n)
{
if(n&1)
res = mul(res,a);
a = mul(a,a);
n >>= 1;
}
return res;
}

int main()
{
int n;
while(~scanf("%d",&n))
{
if(n == -1) break;
a.mat[1][1] = a.mat[1][2] = a.mat[2][1] = 1;
a.mat[2][2] = 0;

matrix ans = pow(a,n);

printf("%d\n",ans.mat[1][2]);
}
return 0;
}