Language:
Fibonacci
Description In the Fibonacci integer sequence, F0 = 0, F1 = 1, and Fn = Fn ? 1 + Fn ? 2 for n ≥ 2. For example, the first ten terms of the Fibonacci sequence are: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, … An alternative formula for the Fibonacci sequence is . Given an integer n, your goal is to compute the last 4 digits of Fn. Input The input test file will contain multiple test cases. Each test case consists of a single line containing n (where 0 ≤ n ≤ 1,000,000,000). The end-of-file is denoted by a single line containing the number ?1. Output For each test case, print the last four digits of Fn. If the last four digits of Fn are all zeros, print ‘0’; otherwise, omit any leading zeros (i.e., print Fn mod 10000). Sample Input 0 9 999999999 1000000000 -1 Sample Output 0 34 626 6875 Hint As a reminder, matrix multiplication is associative, and the product of two 2 × 2 matrices is given by . Also, note that raising any 2 × 2 matrix to the 0th power gives the identity matrix: . Source |
题意:求非波拉契数列第n项mod10000
思路:数据太大,用到矩阵快速幂。
代码:
#include <iostream> #include <cstdio> #include <cstring> #include <algorithm> #include <cmath> #include <string> #include <map> #include <stack> #include <vector> #include <set> #include <queue> #pragma comment (linker,"/STACK:102400000,102400000") #define maxn 1005 #define MAXN 2005 #define mod 10000 #define INF 0x3f3f3f3f #define pi acos(-1.0) #define eps 1e-6 #define lson rt<<1,l,mid #define rson rt<<1|1,mid+1,r #define FRE(i,a,b) for(i = a; i <= b; i++) #define FREE(i,a,b) for(i = a; i >= b; i--) #define FRL(i,a,b) for(i = a; i < b; i++) #define FRLL(i,a,b) for(i = a; i > b; i--) #define mem(t, v) memset ((t) , v, sizeof(t)) #define sf(n) scanf("%d", &n) #define sff(a,b) scanf("%d %d", &a, &b) #define sfff(a,b,c) scanf("%d %d %d", &a, &b, &c) #define pf printf #define DBG pf("Hi\n") typedef long long ll; using namespace std; typedef vector<ll>vec; typedef vector<vec>mat; ll n; mat mul(mat &A,mat &B) { mat C(A.size(),vec(B[0].size())); for (int i=0;i<A.size();i++) { for (int k=0;k<B.size();k++) { for (int j=0;j<B[0].size();j++) C[i][j]=(C[i][j]+A[i][k]*B[k][j])%mod; } } return C; } mat pow(mat A,ll n) { mat B(A.size(),vec(A.size())); for (int i=0;i<A.size();i++) B[i][i]=1; while (n>0) { if (n&1) B=mul(B,A); A=mul(A,A); n>>=1; } return B; } void solve() { mat A(2,vec(2)); A[0][0]=1;A[0][1]=1; A[1][0]=1;A[1][1]=0; A=pow(A,n); pf("%lld\n",(A[1][0]%mod)); } int main() { int i,j; while (scanf("%lld",&n)) { if (n==-1) break; solve(); } return 0; }
原文:http://blog.csdn.net/u014422052/article/details/44684711