/in/foo.cc: In function 'int yg()':
/in/foo.cc:23:20: error: 'k' was not declared in this scope
     in(n),in(m),in(k);
                    ^
/in/foo.cc:25:20: error: expected ';' before 'i'
     for (R int i=1 i<=n; ++i) in(u[i]);
                    ^
/in/foo.cc:25:34: error: 'u' was not declared in this scope
     for (R int i=1 i<=n; ++i) in(u[i]);
                                  ^
/in/foo.cc:29:15: error: invalid types 'int[int]' for array subscript
         c[i][0] = 1;
               ^
/in/foo.cc:30:42: error: invalid types 'int[int]' for array subscript
         for (R int j=1; j<=i; ++j) c[i][j] = (c[i-1][j-1]+c[i-1][j])%M;
                                          ^
/in/foo.cc:30:57: error: invalid types 'int[int]' for array subscript
         for (R int j=1; j<=i; ++j) c[i][j] = (c[i-1][j-1]+c[i-1][j])%M;
                                                         ^
/in/foo.cc:30:67: error: invalid types 'int[int]' for array subscript
         for (R int j=1; j<=i; ++j) c[i][j] = (c[i-1][j-1]+c[i-1][j])%M;
                                                                   ^
/in/foo.cc:30:70: error: 'M' was not declared in this scope
         for (R int j=1; j<=i; ++j) c[i][j] = (c[i-1][j-1]+c[i-1][j])%M;
                                                                      ^
/in/foo.cc:37:12: error: 'rat' was not declared in this scope
         in(rat);
            ^~~
/in/foo.cc:43:36: error: invalid types 'int[int]' for array subscript
                 f[i+1][k] += c[j][k]*c[n-j][n-rat-k]%mod*
                                    ^
/in/foo.cc:43:54: error: 'mod' was not declared in this scope
                 f[i+1][k] += c[j][k]*c[n-j][n-rat-k]%mod*
                                                      ^~~
/in/foo.cc:44:13: error: expected primary-expression before '}' token
             }
             ^