foo.cc: In function 'int main()':
foo.cc:141:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  141 |     for(int i=1;i<n-1;i++)
      |     ^~~
foo.cc:167:9: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
  167 |         printf("%.1lf\n",ret);
      |         ^~~~~~
foo.cc:136:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  136 |     for(int i=0;i<n;i++)scanf("%lf%lf",&pp.x,&pp.y),p1.push_back(pp);
      |                         ~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:137:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  137 |     for(int i=0;i<m;i++)scanf("%lf%lf",&pp.x,&pp.y),p2.push_back(pp);
      |                         ~~~~~^~~~~~~~~~~~~~~~~~~~~~

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