典型的两道矩阵快速幂求斐波那契数列
POJ 那是 默认a=0,b=1
UVA 一般情况是 斐波那契f(n)=(n-1)次幂情况下的(ans.m[0][0] * b + ans.m[0][1] * a);
1 //POJ 2 #include <cstdio> 3 #include <iostream> 4 5 using namespace std; 6 7 const int MOD = 10000; 8 9 struct matrix 10 { 11 int m[2][2]; 12 }ans, base; 13 14 matrix multi(matrix a, matrix b) 15 { 16 matrix tmp; 17 for(int i = 0; i < 2; ++i) 18 { 19 for(int j = 0; j < 2; ++j) 20 { 21 tmp.m[i][j] = 0; 22 for(int k = 0; k < 2; ++k) 23 tmp.m[i][j] = (tmp.m[i][j] + a.m[i][k] * b.m[k][j]) % MOD; 24 } 25 } 26 return tmp; 27 } 28 int fast_mod(int n) // 求矩阵 base 的 n 次幂 29 { 30 base.m[0][0] = base.m[0][1] = base.m[1][0] = 1; 31 base.m[1][1] = 0; 32 ans.m[0][0] = ans.m[1][1] = 1; // ans 初始化为单位矩阵 33 ans.m[0][1] = ans.m[1][0] = 0; 34 while(n) 35 { 36 if(n & 1) //实现 ans *= t; 其中要先把 ans赋值给 tmp,然后用 ans = tmp * t 37 { 38 ans = multi(ans, base); 39 } 40 base = multi(base, base); 41 n >>= 1; 42 } 43 return ans.m[0][1]; 44 } 45 46 int main() 47 { 48 int n; 49 while(scanf("%d", &n) && n != -1) 50 { 51 printf("%d ", fast_mod(n)); 52 } 53 return 0; 54 }
1 //uva 2 #include<cstdio> 3 #include<cstring> 4 #include<algorithm> 5 #include<iostream> 6 #include<cstdlib> 7 #include<string> 8 #include<cmath> 9 #include<vector> 10 using namespace std; 11 const int maxn=1e5+7; 12 const double eps=1e-8; 13 const double pi=acos(-1); 14 #define ll long long 15 const int MOD = 10000; 16 17 int a,b,n,m; 18 struct matrix 19 { 20 int m[2][2]; 21 } ans, base; 22 23 matrix multi(matrix a, matrix b) 24 { 25 matrix tmp; 26 for(int i = 0; i < 2; ++i) 27 { 28 for(int j = 0; j < 2; ++j) 29 { 30 tmp.m[i][j] = 0; 31 for(int k = 0; k < 2; ++k) 32 tmp.m[i][j] = (tmp.m[i][j] + a.m[i][k] * b.m[k][j]) % MOD; 33 } 34 } 35 return tmp; 36 } 37 int fast_mod(int n) // 求矩阵 base 的 n 次幂 38 { 39 base.m[0][0] = base.m[0][1] = base.m[1][0] = 1; 40 base.m[1][1] = 0; 41 ans.m[0][0] = ans.m[1][1] = 1; // ans 初始化为单位矩阵 42 ans.m[0][1] = ans.m[1][0] = 0; 43 while(n) 44 { 45 if(n & 1) //实现 ans *= t; 其中要先把 ans赋值给 tmp,然后用 ans = tmp * t 46 { 47 ans = multi(ans, base); 48 } 49 base = multi(base, base); 50 n >>= 1; 51 } 52 // return ans.m[0][1]; 53 } 54 55 int main() 56 { 57 int t; 58 scanf("%d",&t); 59 while (t--) 60 { 61 scanf("%d%d%d%d",&a,&b,&n,&m); 62 m = pow(10, m); 63 if (n == 0) 64 { 65 printf("%d ", (a%m + m) % m); 66 continue; 67 } 68 if (n == 1) 69 { 70 printf("%d ", (b%m + m) % m); 71 continue; 72 } 73 fast_mod(n-1); 74 int tmp = ((ans.m[0][0] * b + ans.m[0][1] * a) % m + m) % m; 75 printf("%d ", tmp); 76 } 77 return 0; 78 }