foo.cc: In function 'int main()':
foo.cc:16:89: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   for(int i=1;i<=n;i++)scanf("%d%d",&poe[i][0],&poe[i][1]),poe[i][0]+=100,poe[i][1]+=100,dot[poe[i][0]][poe[i][1]]++;
                        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~