Compilare: user.cpp: In function ‘void read()’: user.cpp:14: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:16: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void solve()’: user.cpp:23: warning: ‘st’ may be used uninitialized in this function user.cpp:23: warning: ‘end’ may be used uninitialized in this function