Compilare: main.cpp: In function 'int main()': main.cpp:39:6: warning: unused variable 'nb' [-Wunused-variable] int nb=0; ^~ main.cpp:33:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("darb.in","rt",stdin); ^ main.cpp:34:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("darb.out","wt",stdout); ^ main.cpp:36:16: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&N); ^ main.cpp:42:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&x,&y); ^