记录编号	417501	评测结果	AAAAAAAAAAAAAAAAAAAA
题目名称	数列求值	最终得分	100
用户昵称	HeHe	是否通过	通过
代码语言	C++	运行时间	0.004 s
提交时间	2017-06-25 20:00:45	内存使用	0.57 MiB

#include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;

char buf[1<<18],*fs,*ft;
inline char getc(){return (fs==ft&&(ft=(fs=buf)+fread(buf,1,1<<18,stdin)),fs==ft)?EOF:*fs++;}
inline int in(void){ 
    char tmp = getc();
    int res = 0;
    while(!isdigit(tmp)) tmp = getc();
    while(isdigit(tmp))
        res = (res + (res << 2) << 1) + (tmp ^ 48),
        tmp = getc();
    return res;
}

inline void Pow(int n);

int res[2][2], s[2][2];
int _ans[1][2] = {1, 1};
int ans[1][2];
int N, A, B;

int main(){ 
#ifndef LOCAL
    freopen("sequenceb.in", "r", stdin);
    freopen("sequenceb.out", "w", stdout);
#endif
    A = in(), B = in(), N = in();
    for(int i = 0; i < 2; ++i) res[i][i] = 1;
    s[0][0] = 0;
    s[0][1] = B % 7;
    s[1][0] = 1;
    s[1][1] = A % 7;
    Pow(N - 1);
    for(int i = 0; i < 1; ++i){ 
        for(int j = 0; j < 2; ++j){ 
            for(int k = 0; k < 2; ++k){ 
                ans[i][j] = (ans[i][j] + _ans[i][k] * res[k][j]) % 7;
            }
        }
    }
    printf("%d", ans[0][0]);

    return 0;
}

inline void Pow(int n){ 
    int tmp[2][2];
    while(n){ 
        if(n & 1){ 
            memset(tmp, 0x00, sizeof(tmp));
            for(int i = 0; i < 2; ++i){ 
                for(int j = 0; j < 2; ++j){ 
                    for(int k = 0; k < 2; ++k){ 
                        tmp[i][j] = (tmp[i][j] + res[i][k] * s[k][j]) % 7;
                    }
                }
            }
            for(int i = 0; i < 2; ++i){ 
                for(int j = 0; j < 2; ++j){ 
                    res[i][j] = tmp[i][j];
                }
            }
        }
        memset(tmp, 0x00, sizeof(tmp));
        for(int i = 0; i < 2; ++i){ 
            for(int j = 0; j < 2; ++j){ 
                for(int k = 0; k < 2; ++k){ 
                    tmp[i][j] = (tmp[i][j] + s[i][k] * s[k][j]) % 7;
                }
            }
        }
        for(int i = 0; i < 2; ++i){ 
            for(int j = 0; j < 2; ++j){ 
                s[i][j] = tmp[i][j];
            }
        }
        n >>= 1;
    }
    return ;
}