foo.cc:8:20: error: 'r' has not been declared
    8 | void output(int l, r)
      |                    ^
foo.cc: In function 'void output(int, int)':
foo.cc:10:18: error: 'r' was not declared in this scope
   10 |         if (l == r)
      |                  ^
foo.cc:12:22: error: 'r' was not declared in this scope
   12 |         int x = k[l][r];
      |                      ^
foo.cc: In function 'int main()':
foo.cc:38:29: error: 't' was not declared in this scope
   38 |                         if (t[j] + s[j+1][j+i] > t[j+i] + s[j][j+i-1])
      |                             ^
foo.cc:49:37: error: 't' was not declared in this scope
   49 |                                 if (t[m] + s[j][m-1] * s[m+1][j+i] > s[j][j+i])
      |                                     ^

[Hydro](https://hydro.ac)提供评测服务