foo.cc: In function 'int main()':
foo.cc:11:15: warning: comparison of integer expressions of different signedness: 'int' and 'unsigned int' [-Wsign-compare]
   11 |  for(int i=0;i<n;i++)
      |              ~^~
foo.cc:15:15: warning: comparison of integer expressions of different signedness: 'int' and 'unsigned int' [-Wsign-compare]
   15 |  for(int i=0;i<n;i++)
      |              ~^~
foo.cc:17:16: warning: comparison of integer expressions of different signedness: 'int' and 'unsigned int' [-Wsign-compare]
   17 |   for(int j=i;j<n-1;j++)
      |               ~^~~~

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