/in/foo.cc: In function 'int main()':
/in/foo.cc:30:6: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
      if(!pr[i])
      ^~
/in/foo.cc:32:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
   for(int j=0;j<cnt&&prime[j]*i<=n/2;j++)
   ^~~