foo.cc: In function 'void Build(int, int, int)':
foo.cc:12:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   12 |  int mid=l+r>>1,lc=k<<1,rc=k<<1|1;
      |          ~^~
foo.cc: In function 'void Sq(int, int, int, int, int)':
foo.cc:26:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   26 |  int mid=l+r>>1,lc=k<<1,rc=k<<1|1;
      |          ~^~
foo.cc: In function 'int Query(int, int, int, int, int)':
foo.cc:39:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   39 |  int mid=l+r>>1,lc=k<<1,rc=k<<1|1,ret=0;
      |          ~^~
foo.cc: In function 'int main()':
foo.cc:49:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   49 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
foo.cc:51:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   51 |   scanf("%d",del+i);
      |   ~~~~~^~~~~~~~~~~~
foo.cc:54:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   54 |  scanf("%d",&m);
      |  ~~~~~^~~~~~~~~
foo.cc:58:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   58 |   scanf("%d%d%d",&op,&l,&r);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~
   
  
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