foo.cc: In function 'void maketree(int&, int, int)':
foo.cc:38:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   38 |     int mid=l+r>>1;
      |             ~^~
foo.cc: In function 'void update(int&, int, int, int, int, int, int)':
foo.cc:53:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   53 |     int mid=l+r>>1;
      |             ~^~
foo.cc: In function 'int main()':
foo.cc:112:21: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
  112 |         else if(s[0]='B')
      |                 ~~~~^~~~
foo.cc:90:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   90 |         scanf("%s",s);
      |         ~~~~~^~~~~~~~

Found 6 testcases.
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