Compilare: main.cpp: In function 'int main()': main.cpp:62:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pixy.in" , "r" , stdin); ^ main.cpp:63:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pixy.out" , "w" , stdout); ^ main.cpp:66:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d\n" , &n , &m); ^ main.cpp:71:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%c" , &ch); ^ main.cpp:74:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("\n"); ^