foo.cc: In function 'int main()':
foo.cc:10:45: warning: unused variable 'flag' [-Wunused-variable]
   10 |  int cnt1=0,cnt2=0,left=0,right=len-1,cnt=0,flag=0,max_ans=0,min_ans=0x7fffffff;
      |                                             ^~~~

Found 10 testcases.
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