foo.cc: In function 'int main()':
foo.cc:19:35: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
   19 |                                 if(abs(i-x)+abs(j-y)<=d)
      |                                   ^
foo.cc:11:19: warning: unused variable 'sum' [-Wunused-variable]
   11 |         long long sum=0;
      |                   ^~~

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