/in/foo.cc: In function 'int main()':
/in/foo.cc:19:27: warning: comparison of integer expressions of different signedness: 'int' and 'unsigned int' [-Wsign-compare]
   19 |         for (int i = 1; i <= n; i++) {
      |                         ~~^~~~
/in/foo.cc:24:27: warning: comparison of integer expressions of different signedness: 'int' and 'unsigned int' [-Wsign-compare]
   24 |         for (int i = 1; i < n; i++) {
      |                         ~~^~~
/in/foo.cc:25:39: warning: comparison of integer expressions of different signedness: 'int' and 'unsigned int' [-Wsign-compare]
   25 |                 for (int j = 1; j + i <= n; j++) {
      |                                 ~~~~~~^~~~