Compilare: main.cpp: In function 'int main()': main.cpp:62:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(l = 0 ; l < next1.size() ; l ++) ~~^~~~~~~~~~~~~~ main.cpp:43:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pavare.in" , "r" , stdin); ^ main.cpp:44:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pavare.out" , "w" , stdout); ^ main.cpp:46:35: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d" , &n , &m , &k); ^ main.cpp:49:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d" , &x , &y); ^