Compilare: main.cpp: In function 'int main()': main.cpp:4:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cmmdc.in", "r", stdin); ^ main.cpp:5:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cmmdc.out", "w", stdout); ^ main.cpp:8:40: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &mat[0][0], &mat[1][0]); ^