HDU 4686 Arc of Dream (2013多校9 1001 题,矩阵)

Arc of Dream

Time Limit: 2000/2000 MS (Java/Others)    Memory Limit: 65535/65535 K (Java/Others)
Total Submission(s): 0    Accepted Submission(s): 0


Problem Description
An Arc of Dream is a curve defined by following function:

where
a 0 = A0
a i = a i-1*AX+AY
b 0 = B0
b i = b i-1*BX+BY
What is the value of AoD(N) modulo 1,000,000,007?
 

 

Input
There are multiple test cases. Process to the End of File.
Each test case contains 7 nonnegative integers as follows:
N
A0 AX AY
B0 BX BY
N is no more than 10 18, and all the other integers are no more than 2×10 9.
 

 

Output
For each test case, output AoD(N) modulo 1,000,000,007.
 

 

Sample Input
1 1 2 3 4 5 6 2 1 2 3 4 5 6 3 1 2 3 4 5 6
 

 

Sample Output
4 134 1902
 

 

Author
Zejun Wu (watashi)

 

 

 

 

 

 

很明显是要构造矩阵,然后用矩阵快速幂求解。

 

 

                                                                |   AX   0   AXBY   AXBY  0  |

                                                                |   0   BX  AYBX    AYBX  0  |

{a[i-1]   b[i-1]   a[i-1]*b[i-1]  AoD[i-1]  1}* |   0   0   AXBX    AXBX   0  |  = {a[i]   b[i]   a[i]*b[i]  AoD[i]  1}

                                                               |    0   0     0          1     0    |

                                                               |  AY  BY   AYBY   AYBY   1   |

 

然后就可以搞了

 

注意n==0的时候,输出0

 

  1 /* ***********************************************

  2 Author        :kuangbin

  3 Created Time  :2013/8/20 12:21:51

  4 File Name     :F:\2013ACM练习\2013多校9\1001.cpp

  5 ************************************************ */

  6 

  7 #include <stdio.h>

  8 #include <string.h>

  9 #include <iostream>

 10 #include <algorithm>

 11 #include <vector>

 12 #include <queue>

 13 #include <set>

 14 #include <map>

 15 #include <string>

 16 #include <math.h>

 17 #include <stdlib.h>

 18 #include <time.h>

 19 using namespace std;

 20 const int MOD = 1e9+7;

 21 struct Matrix

 22 {

 23     int mat[5][5];

 24     void clear()

 25     {

 26         memset(mat,0,sizeof(mat));

 27     }

 28     void output()

 29     {

 30         for(int i = 0;i < 5;i++)

 31         {

 32             for(int j = 0;j < 5;j++)

 33                 printf("%d ",mat[i][j]);

 34             printf("\n");

 35         }

 36     }

 37     Matrix operator *(const Matrix &b)const

 38     {

 39         Matrix ret;

 40         for(int i = 0;i < 5;i++)

 41             for(int j = 0;j < 5;j++)

 42             {

 43                 ret.mat[i][j] = 0;

 44                 for(int k = 0;k < 5;k++)

 45                 {

 46                     long long tmp = (long long)mat[i][k]*b.mat[k][j]%MOD;

 47                     ret.mat[i][j] = (ret.mat[i][j]+tmp);

 48                     if(ret.mat[i][j]>MOD)

 49                         ret.mat[i][j] -= MOD;

 50                 }

 51             }

 52         return ret;

 53     }

 54 };

 55 Matrix pow_M(Matrix a,long long n)

 56 {

 57     Matrix ret;

 58     ret.clear();

 59     for(int i = 0;i < 5;i++)

 60         ret.mat[i][i] = 1;

 61     Matrix tmp = a;

 62     while(n)

 63     {

 64         if(n&1)ret = ret*tmp;

 65         tmp = tmp*tmp;

 66         n>>=1;

 67     }

 68     return ret;

 69 }

 70 int main()

 71 {

 72     //freopen("in.txt","r",stdin);

 73     //freopen("out.txt","w",stdout);

 74     long long n;

 75     int A0,AX,AY;

 76     int B0,BX,BY;

 77     while(scanf("%I64d",&n) == 1)

 78     {

 79         scanf("%d%d%d",&A0,&AX,&AY);

 80         scanf("%d%d%d",&B0,&BX,&BY);

 81         if(n == 0)

 82         {

 83             printf("0\n");

 84             continue;

 85         }

 86         Matrix a;

 87         a.clear();

 88         a.mat[0][0] = AX%MOD;

 89         a.mat[0][2] = (long long)AX*BY%MOD;

 90         a.mat[1][1] = BX%MOD;

 91         a.mat[1][2] = (long long)AY*BX%MOD;

 92         a.mat[2][2] = (long long)AX*BX%MOD;

 93         a.mat[3][3] = 1;

 94         a.mat[4][0] = AY%MOD;

 95         a.mat[4][1] = BY%MOD;

 96         a.mat[4][2] = (long long)AY*BY%MOD;

 97         a.mat[4][4] = 1;

 98         a.mat[0][3] = a.mat[0][2];

 99         a.mat[1][3] = a.mat[1][2];

100         a.mat[2][3] = a.mat[2][2];

101         a.mat[4][3] = a.mat[4][2];

102         //a.output();

103         a = pow_M(a,n-1);

104         //a.output();

105         long long t1 = (long long)A0*B0%MOD;

106         long long ans = t1*a.mat[2][3]%MOD + t1*a.mat[3][3]%MOD;

107         if(ans > MOD)ans -= MOD;

108         ans += (long long)A0*a.mat[0][3];

109         ans %= MOD;

110         ans += (long long)B0*a.mat[1][3];

111         ans %= MOD;

112         ans += (long long)a.mat[4][3];

113         ans %= MOD;

114         printf("%d\n",(int)ans);

115     }

116     return 0;

117 }

 

 

 

 

 

 

 

 

 

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