View Compilation Error

0_0_30522115_2644.cpp: In member function 'matrix matrix::operator*(const matrix&) const':
0_0_30522115_2644.cpp:29:87: error: 'ep' was not declared in this scope
                             res.mat[i][j]=(res.mat[i][j]+(this->mat[i][k]*b.mat[k][j]%ep)%ep;
                                                                                       ^
0_0_30522115_2644.cpp:29:93: error: expected ')' before ';' token
                             res.mat[i][j]=(res.mat[i][j]+(this->mat[i][k]*b.mat[k][j]%ep)%ep;
                                                                                             ^
0_0_30522115_2644.cpp:34:39: error: 'ep' was not declared in this scope
                 if((this->mat[1][1])>=ep)
                                       ^
0_0_30522115_2644.cpp: In function 'void solve()':
0_0_30522115_2644.cpp:99:17: error: 'ep' was not declared in this scope
             u=u%ep+ep;
                 ^
0_0_30522115_2644.cpp:110:17: error: 'ep' was not declared in this scope
             u=u%ep+ep;
                 ^
0_0_30522115_2644.cpp: In function 'int main()':
0_0_30522115_2644.cpp:129:9: error: 'ep' was not declared in this scope
         ep=euler(p);//printf("ep=%d\n",ep);
         ^