/in/foo.cc: In constructor 'Mat::Mat()':
/in/foo.cc:12:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 1; i <= n; ++i)
                   ~~^~~~
/in/foo.cc:13:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int j = 1; j <= n; ++j)
                    ~~^~~~
/in/foo.cc: In member function 'Mat Mat::operator*(Mat)':
/in/foo.cc:20:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 1; i <= n; ++i)
                   ~~^~~~
/in/foo.cc:21:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int j = 1; j <= n; ++j)
                    ~~^~~~
/in/foo.cc:22:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int k = 1; k <= n; ++k)
                     ~~^~~~
/in/foo.cc: In member function 'void Mat::printMat()':
/in/foo.cc:29:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 1; i <= n; ++i)
                   ~~^~~~
/in/foo.cc:31:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int j = 1; j <= n; ++j)
                    ~~^~~~
/in/foo.cc:32:30: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long long unsigned int' [-Wformat=]
     printf("%d ", value[i][j]);
                              ^
/in/foo.cc: In function 'Mat power(Mat, long long unsigned int)':
/in/foo.cc:63:13: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
   if (m & 1 == 1)
           ~~^~~~