Compilare: main.cpp: In function 'int main()': main.cpp:63:13: warning: unused variable 'j' [-Wunused-variable] int i , j; ^ main.cpp:64:40: 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:65:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d" , &n , &m); ^ main.cpp:67:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ("%s" , s); ^