Compilare: user.cpp: In function ‘int main()’: user.cpp:53:15: warning: unused variable ‘j’ [-Wunused-variable] int k,l,i,j,a,a1,a2,t,dist; ^ user.cpp:53:17: warning: unused variable ‘a’ [-Wunused-variable] int k,l,i,j,a,a1,a2,t,dist; ^ user.cpp:53:25: warning: unused variable ‘t’ [-Wunused-variable] int k,l,i,j,a,a1,a2,t,dist; ^ user.cpp:53:27: warning: unused variable ‘dist’ [-Wunused-variable] int k,l,i,j,a,a1,a2,t,dist; ^ user.cpp:54:36: 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:55:38: 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:56:38: 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:58:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &a1, &a2); ^