Compilare: user.cpp: In function ‘int main()’: user.cpp:10:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,x,y,k,start,stop; ^ user.cpp:10:25: warning: unused variable ‘stop’ [-Wunused-variable] int i,j,x,y,k,start,stop; ^ user.cpp:8:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dijkstra.in","r",stdin); ^ user.cpp:9:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dijkstra.out","w",stdout); ^ user.cpp:11:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:14:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&x,&y,&k); ^ user.cpp:10:19: warning: ‘start’ may be used uninitialized in this function [-Wmaybe-uninitialized] int i,j,x,y,k,start,stop; ^