foo.cc: In function 'int main()':
foo.cc:61:20: warning: comparison of integer expressions of different signedness: 'int' and 'long long unsigned int' [-Wsign-compare]
   61 |  for (int i = 2; i <= n / 2 + 1; i++) {
      |                  ~~^~~~~~~~~~~~
foo.cc:63:9: warning: comparison of integer expressions of different signedness: 'int' and 'long long unsigned int' [-Wsign-compare]
   63 |   if (i == p) {
      |       ~~^~~~

Found 30 testcases.
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