Compilare: user.cpp: In function ‘int main()’: user.cpp:72:15: warning: unused variable ‘i’ [-Wunused-variable] int n,m,k,i,j,q,x1,y1,x2,y2,val; ^ user.cpp:72:17: warning: unused variable ‘j’ [-Wunused-variable] int n,m,k,i,j,q,x1,y1,x2,y2,val; ^ user.cpp:70:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dreptunghiuri3.in","r",stdin); ^ user.cpp:71:45: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dreptunghiuri3.out","w",stdout); ^ user.cpp:74:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d\n",&n,&m,&k); ^ user.cpp:79:17: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(si); ^ /tmp/ccrKAAI3.o: In function `main': user.cpp:(.text.startup+0xba): warning: the `gets' function is dangerous and should not be used.