运行 ID: 335578

Main.cc: In function ‘int main()’:
Main.cc:21:8: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses]
   mid=l+r>>1;       
       ~^~
Main.cc:22:6: error: ‘ck’ was not declared in this scope
   if(ck(mid)) l=mid+1;     
      ^~
Main.cc:22:6: note: suggested alternative: ‘c’
   if(ck(mid)) l=mid+1;     
      ^~
      c