Compilare: user.cpp: In function ‘void readdata()’: user.cpp:17:21: warning: format ‘%d’ expects argument of type ‘int*’, but argument 3 has type ‘long int*’ [-Wformat=] fscanf(f,"%d",&n); ^ user.cpp:20:40: warning: format ‘%d’ expects argument of type ‘int*’, but argument 3 has type ‘long int*’ [-Wformat=] fscanf(f,"%d%d",&v[i].x,&v[i].y); ^ user.cpp:20:40: warning: format ‘%d’ expects argument of type ‘int*’, but argument 4 has type ‘long int*’ [-Wformat=] user.cpp: In function ‘void writedata()’: user.cpp:67:21: warning: format ‘%d’ expects argument of type ‘int’, but argument 3 has type ‘long int’ [-Wformat=] fprintf(f,"%d",d); ^ user.cpp: In function ‘void readdata()’: user.cpp:17:22: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&n); ^ user.cpp:20:41: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d",&v[i].x,&v[i].y); ^