foo.cc: In function 'int qmax(int&, int)':
foo.cc:3:38: warning: no return statement in function returning non-void [-Wreturn-type]
 int qmax(int &x,int y) {if (x<y) x=y;}
                                      ^
foo.cc: In function 'int qmin(int&, int)':
foo.cc:4:38: warning: no return statement in function returning non-void [-Wreturn-type]
 int qmin(int &x,int y) {if (x>y) x=y;}
                                      ^
foo.cc: In function 'int read()':
foo.cc:9:5: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
     if(s==EOF)exit(0);if(s=='-')base=-1,s=getchar();
     ^~
foo.cc:9:23: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
     if(s==EOF)exit(0);if(s=='-')base=-1,s=getchar();
                       ^~
foo.cc: In function 'int dfs(int, int)':
foo.cc:46:5: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
     if (u==T||low==0) return low;int used=0,v,W;
     ^~
foo.cc:46:34: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
     if (u==T||low==0) return low;int used=0,v,W;
                                  ^~~

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