Compilare: main.cpp: In function 'int main()': main.cpp:66:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("barbar.in" , "r" , stdin); ^ main.cpp:67:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d" , &n , &m); ^ main.cpp:69:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ("%s" , s); ^ main.cpp:103:5: warning: 'found' may be used uninitialized in this function [-Wmaybe-uninitialized] if (! found) ^~