Compilare: main.cpp: In function 'int main()': main.cpp:21:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ssdj.in", "r", stdin); freopen("ssdj.out", "w", stdout); ^ main.cpp:21:66: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ssdj.in", "r", stdin); freopen("ssdj.out", "w", stdout); ^ main.cpp:23:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ main.cpp:27:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf(" %c", &a[i][j]); ^