foo.cc:26:23: error: extended character — is not valid in an identifier
   26 |         for(int i=n;i;i—-){
      |                       ^
foo.cc: In function 'bool dfs(int, int)':
foo.cc:26:23: error: 'i\U00002014' was not declared in this scope
   26 |         for(int i=n;i;i—-){
      |                       ^~
foo.cc:26:26: error: expected primary-expression before ')' token
   26 |         for(int i=n;i;i—-){
      |                          ^
foo.cc: At global scope:
foo.cc:38:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   38 | main(){int tests=1;//tests=read();
      | ^~~~
foo.cc: In function 'int main()':
foo.cc:55:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   55 |                 int mid=l+r>>1;
      |                         ~^~

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