Runtime Error
/in/foo.cc: In function 'int main()':
/in/foo.cc:34:11: warning: 'u' may be used uninitialized in this function [-Wmaybe-uninitialized]
book[u]=1;
~~~~~~~^~
/in/foo.cc: In function 'int main()':
/in/foo.cc:34:11: warning: 'u' may be used uninitialized in this function [-Wmaybe-uninitialized]
book[u]=1;
~~~~~~~^~
