Compilare: user.cpp: In function ‘int main()’: user.cpp:21:9: warning: unused variable ‘m1’ [-Wunused-variable] int m1=0; ^ user.cpp:22:9: warning: unused variable ‘m2’ [-Wunused-variable] int m2=0; ^ user.cpp:23:9: warning: unused variable ‘m1p’ [-Wunused-variable] int m1p=0; ^ user.cpp:24:9: warning: unused variable ‘m2p’ [-Wunused-variable] int m2p=0; ^ user.cpp:12:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("lacusta.in","r",stdin); ^ user.cpp:13:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("lacusta.out","w",stdout); ^ user.cpp:15:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&N,&M); ^ user.cpp:19:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d ",&v[i][j]); ^