/in/foo.cc: In function 'void FindPrimeSumPair(int, int, int)':
/in/foo.cc:98:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if (min_sum == n*(2*n-1)) {
             ~~~~~~~~^~~~~~~~~~~~
/in/foo.cc:102:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if (min_sum == n*(2*n-1)+1) {
             ~~~~~~~~^~~~~~~~~~~~~~