Compilare: user.cpp: In function ‘void Dijkstra()’: user.cpp:25:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( i = 0 ; i < G[x].size() ; i++ ) ^ user.cpp:14:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,k,val,x; ^ user.cpp:14:13: warning: unused variable ‘k’ [-Wunused-variable] int i,j,k,val,x; ^ user.cpp: In function ‘int main()’: user.cpp:36:37: 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:37:39: 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:40:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n",&N,&M); ^ user.cpp:43:37: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d\n",&a,&b,&c); ^