Compilare: user.cpp: In function ‘int main()’: user.cpp:26:8: warning: unused variable ‘j’ [-Wunused-variable] {int i,j,x,y; ^ user.cpp:27:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d",&n,&m); ^ user.cpp:28:40: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (i=1;i<=n;i++) fscanf(f,"%d",&v[i]); ^ user.cpp:29:44: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (i=1;i<=m;i++) {fscanf(f,"%d %d",&y,&x); ^