Compilare: user.cpp: In function ‘int main()’: user.cpp:53:19: warning: unused variable ‘dist’ [-Wunused-variable] int a1,a2,dist; ^ user.cpp:55:19: warning: unused variable ‘x3’ [-Wunused-variable] int x1,x2,x3,x4; ^ user.cpp:55:22: warning: unused variable ‘x4’ [-Wunused-variable] int x1,x2,x3,x4; ^ user.cpp:48:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("marmote.in","r",stdin); ^ user.cpp:49:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("marmote.out","w",stdout); ^ user.cpp:51:37: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d",&n,&m,&k,&l); ^ user.cpp:54:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&a1,&a2); ^