Compilare: user.cpp: In function ‘int main()’: user.cpp:5:26: warning: unused variable ‘j’ [-Wunused-variable] int a,b,u,x1,y1,x2,y2,i,j,n,m,l,ok,nr=0,mr=0,p,q; ^ user.cpp:5:30: warning: unused variable ‘m’ [-Wunused-variable] int a,b,u,x1,y1,x2,y2,i,j,n,m,l,ok,nr=0,mr=0,p,q; ^ user.cpp:5:34: warning: variable ‘ok’ set but not used [-Wunused-but-set-variable] int a,b,u,x1,y1,x2,y2,i,j,n,m,l,ok,nr=0,mr=0,p,q; ^ user.cpp:5:42: warning: unused variable ‘mr’ [-Wunused-variable] int a,b,u,x1,y1,x2,y2,i,j,n,m,l,ok,nr=0,mr=0,p,q; ^ user.cpp:5:47: warning: unused variable ‘p’ [-Wunused-variable] int a,b,u,x1,y1,x2,y2,i,j,n,m,l,ok,nr=0,mr=0,p,q; ^ user.cpp:5:49: warning: unused variable ‘q’ [-Wunused-variable] int a,b,u,x1,y1,x2,y2,i,j,n,m,l,ok,nr=0,mr=0,p,q; ^ user.cpp:8:31: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d %d",&a,&b,&u); ^ user.cpp:11:28: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d",&x1,&y1); ^ user.cpp:18:42: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d %d %d",&x1,&y1,&x2,&y2); ^ user.cpp:15:2: warning: ‘n’ may be used uninitialized in this function [-Wmaybe-uninitialized] for (l=1;l<=n;l++) ^