stones.cpp: In function 'int main()':
stones.cpp:57:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if (x1 > x2 && x2 == 0 && x1 == q.size())
~~~^~~~~~~~~~~
stones.cpp:60:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if (x1 < x2 && x1 == 0 && x2 == v.size())
~~~^~~~~~~~~~~
stones.cpp:12:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
freopen ("stones.in" , "r" , stdin) ;
~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
stones.cpp:13:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
freopen ("stones.out" , "w" , stdout) ;
~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
stones.cpp:14:12: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf ("%d" , &n) ;
~~~~~~^~~~~~~~~~~
stones.cpp:19:16: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf ("%d%d" , &x , &a) ;
~~~~~~^~~~~~~~~~~~~~~~~~