Compilare: main.cpp: In function 'int main()': main.cpp:42:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<G[fi].size();i++) ~^~~~~~~~~~~~~ main.cpp:21:19: warning: variable 'tot' set but not used [-Wunused-but-set-variable] int n,m,a,b,c,tot,i; ^~~ main.cpp:19:37: 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); ^ main.cpp:20:39: 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); ^ main.cpp:23:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ main.cpp:26:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&a,&b,&c); ^