1.applying non-zero offset to null pointer：
详细信息：
runtime error: applying non-zero offset 18446744073709551615 to null pointer (basic_string.h)
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior /usr/bin/../lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/basic_string.h:527:69
解决方案：
在函数中该返回string的地方返回了int。尤其注意是不是return "0"写成了return 0
2.无法引用默认构造函数，它的构造函数已经被删除。
解决方案：
在类中声明了没有构造函数的变量，比如unordered_set<pair<int,int>> us;
3.error: request for member '..' in '..' , which is of non-class type
解决方案：查看priority_queue的比较函数是否写正确
4.terminate called after throwing an instance of 'std::invalid_argument' what(): stoi
解决方案：查看stoi的字符串是否合法。
5.error: call to deleted constructor of 'std::stringstream' (aka 'basic_stringstream')
/usr/bin/../lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/sstream:787:7: note: 'basic_stringstream' has been explicitly marked deleted here
basic_stringstream(const basic_stringstream&) = delete;
解决方案：传stringstream时传入引用值
