Compilare: main.cpp: In function 'int main()': main.cpp:7:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("piata.in" , "r" ,stdin); ^ main.cpp:8:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("piata.out" , "w" ,stdout); ^ main.cpp:9:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &n); ^ main.cpp:10:44: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d" , &ax , &ay , &bx , &by); ^