Compilare: user.cpp: In function ‘int main()’: user.cpp:24:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,n,m,nr,step,temp; ^ user.cpp:21:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("drum6.in","r",stdin); ^ user.cpp:22:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("drum6.out","w",stdout); ^ user.cpp:27:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:28:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c",&go); ^ user.cpp:30:61: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] for( i = 1; i <= n; ++i ) fgets( a[i] + 1, NMax, stdin ); ^